A week's worth of learning: multiple ways to download files

A week's worth of learning: multiple ways to download files

[[151719]]

This article mainly includes the following contents:

(1) Direct method using NSURLConnection

(2) Using NSURLConnection proxy method

(3) Direct method using NSURLSession

(4) Using NSURLSession proxy method

(5) Using AFNetworking

Additional features:

(1) Use AFNetworkReachabilityManager in AFNetworking to check the network status:

  • AFNetworkReachabilityStatusReachableViaWiFi: Wi-Fi network

  • AFNetworkReachabilityStatusReachableViaWWAN: 2G/3G/4G cellular network

  • AFNetworkReachabilityStatusNotReachable: Not connected to the network

(2) Use AFNetworkActivityIndicatorManager in AFNetworking to start the network activity indicator:

  1.  # import   "AFNetworkActivityIndicatorManager.h"  
  2.  //Start the network activity indicator; it will display or hide the network activity indicator in real time according to the network interaction situation; it uses the "notification and message mechanism" to implement the control of [UIApplication sharedApplication].networkActivityIndicatorVisible  
  3.  [AFNetworkActivityIndicatorManager sharedManager].enabled = YES;

The effect is as follows:

ViewController.h

  1.  # import   @interface ViewController: UITableViewController
  2.  @property (copy, nonatomic) NSArray *arrSampleName; 
  3.   
  4.  - (instancetype)initWithSampleNameArray:(NSArray *)arrSampleName; 
  5.   
  6.  @end  

ViewController.m

  1.  # import   "ViewController.h"  
  2.  # import   "NSURLConnectionViewController.h"  
  3.  # import   "NSURLConnectionDelegateViewController.h"  
  4.  # import   "NSURLSessionViewController.h"  
  5.  # import   "NSURLSessionDelegateViewController.h"  
  6.  # import   "AFNetworkingViewController.h"   
  7.   
  8.  @interface ViewController ()
  9.  - ( void )layoutUI;
  10.  @end   
  11.   
  12.  @implementation ViewController
  13.  - ( void )viewDidLoad {
  14.  [ super viewDidLoad]; 
  15.       
  16.  [self layoutUI];
  17.  } 
  18.   
  19.  - ( void )didReceiveMemoryWarning {
  20.     [ super didReceiveMemoryWarning];
  21.  // Dispose of any resources that can be recreated.  
  22.  } 
  23.   
  24.  - (instancetype)initWithSampleNameArray:(NSArray *)arrSampleName {
  25.  if (self = [ super initWithStyle:UITableViewStyleGrouped]) {
  26.  self.navigationItem.title = @ "Multiple ways to implement file download function" ;
  27.         self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@ "return" style:UIBarButtonItemStylePlain target:nil action:nil]; 
  28.           
  29.         _arrSampleName = arrSampleName;
  30.  }
  31.  return self;
  32.  } 
  33.   
  34.  - ( void )layoutUI {
  35.  } 
  36.   
  37.  #pragma mark - UITableViewController related method rewrite
  38.  - (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section {
  39.  return   0.1 ;
  40.  } 
  41.   
  42.  - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
  43.  return   1 ;
  44.  } 
  45.   
  46.  - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
  47.  return [_arrSampleName count];
  48.  } 
  49.   
  50.  - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
  51.  static NSString *cellIdentifier = @ "cell" ;
  52.     UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
  53.  if (!cell) {
  54.         cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
  55.  }
  56.     cell.textLabel.text = _arrSampleName[indexPath.row];
  57.  return cell;
  58.  } 
  59.   
  60.  - ( void )tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
  61.  switch (indexPath.row) {
  62.  case   0 : {
  63.             NSURLConnectionViewController *connectionVC = [NSURLConnectionViewController new ];
  64.             [self.navigationController pushViewController:connectionVC animated:YES];
  65.  break ;
  66.  }
  67.  case   1 : {
  68.             NSURLConnectionDelegateViewController *connectionDelegateVC = [NSURLConnectionDelegateViewController new ];
  69.             [self.navigationController pushViewController:connectionDelegateVC animated:YES];
  70.  break ;
  71.  }
  72.  case   2 : {
  73.             NSURLSessionViewController *sessionVC = [NSURLSessionViewController new ];
  74.             [self.navigationController pushViewController:sessionVC animated:YES];
  75.  break ;
  76.  }
  77.  case   3 : {
  78.             NSURLSessionDelegateViewController *sessionDelegateVC = [NSURLSessionDelegateViewController new ];
  79.             [self.navigationController pushViewController:sessionDelegateVC animated:YES];
  80.  break ;
  81.  }
  82.  case   4 : {
  83.             AFNetworkingViewController *networkingVC = [AFNetworkingViewController new ];
  84.             [self.navigationController pushViewController:networkingVC animated:YES];
  85.  break ;
  86.  }
  87.  default :
  88.  break ;
  89.  }
  90.  } 
  91.   
  92.  @end  

PrefixHeader.pch

  1.  #define kFileURLStr @ "http://files.cnblogs.com/files/huangjianwu/metro_demoUse Highcharts to implement chart display.zip"   
  2.   
  3.  #define kTitleOfNSURLConnection @ "Use NSURLConnection directly"  
  4.  #define kTitleOfNSURLConnectionDelegate @ "Use NSURLConnection delegate method"  
  5.  #define kTitleOfNSURLSession @ "Use NSURLSession directly"  
  6.  #define kTitleOfNSURLSessionDelegate @ "Use NSURLSession delegate method"  
  7.  #define kTitleOfAFNetworking @ "How to use AFNetworking"   
  8.   
  9.  #define kApplication [UIApplication sharedApplication]

UIButton+BeautifulButton.h

  1.  # import   @interfaceUIButton (BeautifulButton)
  2.  /**
  3.  * According to the button text color, return the rounded button of the corresponding text color
  4.  *
  5.  * @param tintColor button text color; if nil, it will be dark gray
  6.  */  
  7.  - ( void )beautifulButton:(UIColor *)tintColor; 
  8.   
  9.  @end  

UIButton+BeautifulButton.m

  1.  # import   "UIButton+BeautifulButton.h"   
  2.   
  3.  @implementationUIButton (BeautifulButton) 
  4.   
  5.  - ( void )beautifulButton:(UIColor *)tintColor {
  6.     self.tintColor = tintColor ?: [UIColor darkGrayColor];
  7.     self.layer.masksToBounds = YES;
  8.     self.layer.cornerRadius = 10.0 ;
  9.     self.layer.borderColor = [UIColor grayColor].CGColor;
  10.     self.layer.borderWidth = 1.0 ;
  11.  } 
  12.   
  13.  @end  

NSURLConnectionViewController.h

  1.  # import   @interface NSURLConnectionViewController : UIViewController
  2.  @property (strong, nonatomic) IBOutlet UILabel *lblFileName;
  3.  @property (strong, nonatomic) IBOutlet UILabel *lblMessage;
  4.  @property (strong, nonatomic) IBOutlet UIButton *btnDownloadFile; 
  5.   
  6.  @end  

NSURLConnectionViewController.m

  1.  # import   "NSURLConnectionViewController.h"  
  2.  # import   "UIButton+BeautifulButton.h"   
  3.   
  4.  @interface NSURLConnectionViewController ()
  5.  - ( void )layoutUI;
  6.  - ( void )saveDataToDisk:(NSData *)data;
  7.  @end   
  8.   
  9.  @implementation NSURLConnectionViewController 
  10.   
  11.  - ( void )viewDidLoad {
  12.  [ super viewDidLoad]; 
  13.       
  14.  [self layoutUI];
  15.  } 
  16.   
  17.  - ( void )didReceiveMemoryWarning {
  18.     [ super didReceiveMemoryWarning];
  19.  // Dispose of any resources that can be recreated.  
  20.  } 
  21.   
  22.  - ( void )layoutUI {
  23.     self.navigationItem.title = kTitleOfNSURLConnection;
  24.     self.view.backgroundColor = [UIColor colorWithWhite: 0.95 alpha: 1.000 ]; 
  25.       
  26.     [_btnDownloadFile beautifulButton:nil];
  27.  } 
  28.   
  29.  - ( void )saveDataToDisk:(NSData *)data {
  30.  //Save the file after receiving the data; note Apple's official requirement: downloaded data can only be saved in the cache directory (/Library/Caches)  
  31.     NSString *savePath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject];
  32.     savePath = [savePath stringByAppendingPathComponent:_lblFileName.text];
  33.  [data writeToFile:savePath atomically:YES]; //writeToFile: method: If the savePath file exists, it will overwrite it  
  34.  } 
  35.   
  36.  - (IBAction)downloadFile:(id)sender {
  37.  _lblMessage.text = @ "Downloading..." ; 
  38.       
  39.     NSString *fileURLStr = kFileURLStr;
  40.  //Encoding operation; the corresponding decoding operation is to use the stringByRemovingPercentEncoding method  
  41.     fileURLStr = [fileURLStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
  42.     NSURL *fileURL = [NSURL URLWithString:fileURLStr]; 
  43.       
  44.  //Create request  
  45.     NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:fileURL]; 
  46.       
  47.  //Create a connection; Apple provides two methods for handling general requests. They do not require a series of NSURLConnectionDataDelegate delegate protocol method operations, which are concise and intuitive.  
  48.  //Method 1: Send a synchronous request; not recommended, because if the current thread is the main thread, it will cause thread blocking, generally less used  
  49.  // NSURLResponse *response;  
  50.  // NSError *connectionError;  
  51.  // NSData *data = [NSURLConnection sendSynchronousRequest:request  
  52.  // returningResponse:&response  
  53.  // error:&connectionError];  
  54.  // if (!connectionError) {  
  55.  // [self saveDataToDisk:data];  
  56.  // NSLog(@"Save successfully");  
  57.  //  
  58.  // _lblMessage.text = @"Download completed";  
  59.  // } else {  
  60.  // NSLog(@"Download failed, error message: %@", connectionError.localizedDescription);  
  61.  //  
  62.  // _lblMessage.text = @"Download failed";  
  63.  // }   
  64.       
  65.  //Method 2: Send an asynchronous request  
  66.     [NSURLConnection sendAsynchronousRequest:request
  67.                                        queue:[NSOperationQueue mainQueue]
  68.                            completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
  69.  if (!connectionError) {
  70.                                    [self saveDataToDisk:data];
  71.  NSLog(@ "Save successfully" ); 
  72.                                      
  73.  _lblMessage.text = @ "Download completed" ; 
  74.                                      
  75.                                } else {
  76.  NSLog(@ "Download failed, error message: %@" , connectionError.localizedDescription); 
  77.                                      
  78.  _lblMessage.text = @ "Download failed" ;
  79.                                }
  80.                            }];
  81.  } 
  82.   
  83.  @end  

#p#

NSURLConnectionViewController.xib

  1.  [?xml version= "1.0" encoding= "UTF-8" standalone= "no" ?]
  2.  [document type= "com.apple.InterfaceBuilder3.CocoaTouch.XIB" version= "3.0" toolsVersion= "6211" systemVersion= "14A298i" targetRuntime= "iOS.CocoaTouch" propertyAccessControl= "none" useAutolayout= "YES" useTraitCollections= "YES" ]
  3.  [dependencies]
  4.         [plugIn identifier= "com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version= "6204" /]
  5.  [/dependencies]
  6.  [objects]
  7.         [placeholder placeholderIdentifier= "IBFilesOwner" id= "-1" userLabel= "File's Owner" customClass= "NSURLConnectionViewController" ]
  8.  [connections]
  9.                 [outlet property= "btnDownloadFile" destination= "mwt-p9-tRE" id= "ZVc-6S-ES3" /]
  10.                 [outlet property= "lblFileName" destination= "dlB-Qn-eOO" id= "NdS-9n-7KX" /]
  11.                 [outlet property= "lblMessage" destination= "qlQ-nM-BXU" id= "tRe-SR-AQE" /]
  12.                 [outlet property= "view" destination= "i5M-Pr-FkT" id= "sfx-zR-JGt" /]
  13.  [/connections]
  14.  [/placeholder]
  15.         [placeholder placeholderIdentifier= "IBFirstResponder" id= "-2" customClass= "UIResponder" /]
  16.         [view clearsContextBeforeDrawing= "NO" contentMode= "scaleToFill" id= "i5M-Pr-FkT" ]
  17.             [rect key= "frame" x= "0.0" y= "0.0" width= "600" height= "600" /]
  18.             [autoresizingMask key= "autoresizingMask" widthSizable= "YES" heightSizable= "YES" /]
  19.  [subviews]
  20.                 [label opaque= "NO" userInteractionEnabled= "NO" contentMode= "left" horizontalHuggingPriority= "251" verticalHuggingPriority= "251" text= "metro_demo uses Highcharts to implement chart display.zip" lineBreakMode= "tailTruncation" baselineAdjustment= "alignBaselines" adjustsFontSizeToFit= "NO" translatesAutoresizingMaskIntoConstraints= "NO" id= "dlB-Qn-eOO" ]
  21.                     [rect key= "frame" x= "145" y= "104" width= "309.5" height= "18" /]
  22.                     [fontDescription key= "fontDescription" type= "boldSystem" pointSize= "15" /]
  23.                     [color key= "textColor" cocoaTouchSystemColor= "darkTextColor" /]
  24.                     [nil key= "highlightedColor" /]
  25.  [/label]
  26.                 [button opaque= "NO" contentMode= "scaleToFill" contentHorizontalAlignment= "center" contentVerticalAlignment= "center" buttonType= "roundedRect" lineBreakMode= "middleTruncation" translatesAutoresizingMaskIntoConstraints= "NO" id= "mwt-p9-tRE" ]
  27.                     [rect key= "frame" x= "250" y= "520" width= "100" height= "40" /]
  28.                     [constraints]
  29.                         [constraint firstAttribute= "width" constant= "100" id= "I5D-tA-ffH" /]
  30.                         [constraint firstAttribute= "height" constant= "40" id= "Y8C-D4-IVr" /]
  31.                     [/constraints]
  32.  [state key= "normal" title= "Download" ]
  33.                         [color key= "titleShadowColor" white= "0.5" alpha= "1" colorSpace= "calibratedWhite" /]
  34.  [/state]
  35.                     [connections]
  36.                         [action selector= "downloadFile:" destination= "-1" eventType= "touchUpInside" id= "MK4-Yk-IOk" /]
  37.                     [/connections]
  38.  [/button]
  39.                 [label opaque= "NO" userInteractionEnabled= "NO" contentMode= "left" horizontalHuggingPriority= "251" verticalHuggingPriority= "251" text= "Label" lineBreakMode= "tailTruncation" baselineAdjustment= "alignBaselines" adjustsFontSizeToFit= "NO" translatesAutoresizingMaskIntoConstraints= "NO" id= "qlQ-nM-BXU" ]
  40.                     [rect key= "frame" x= "145" y= "140" width= "37.5" height= "18" /]
  41.                     [fontDescription key= "fontDescription" type= "system" pointSize= "15" /]
  42.                     [color key= "textColor" red= "0.0" green= "0.50196081399917603" blue= "1" alpha= "1" colorSpace= "calibratedRGB" /]
  43.                     [nil key= "highlightedColor" /]
  44.                     [userDefinedRuntimeAttributes]
  45.                         [userDefinedRuntimeAttribute type= "string" keyPath= "text" value= "" /]
  46.                     [/userDefinedRuntimeAttributes]
  47.  [/label]
  48.  [/subviews]
  49.             [color key= "backgroundColor" white= "1" alpha= "1" colorSpace= "custom" customColorSpace= "calibratedWhite" /]
  50.  [constraints]
  51.                 [constraint firstAttribute= "centerX" secondItem= "dlB-Qn-eOO" secondAttribute= "centerX" id= "gNK-NO-rth" /]
  52.                 [constraint firstItem= "dlB-Qn-eOO" firstAttribute= "top" secondItem= "i5M-Pr-FkT" secondAttribute= "top" constant= "104" id= "hwU-O2-Fed" /]
  53.                 [constraint firstAttribute= "centerX" secondItem= "mwt-p9-tRE" secondAttribute= "centerX" id= "teN-3t-8Gc" /]
  54.                 [constraint firstItem= "qlQ-nM-BXU" firstAttribute= "top" secondItem= "i5M-Pr-FkT" secondAttribute= "top" constant= "140" id= "w3g-ej-P18" /]
  55.                 [constraint firstItem= "dlB-Qn-eOO" firstAttribute= "leading" secondItem= "qlQ-nM-BXU" secondAttribute= "leading" constant= "0.5" id= "wMU-pU-z9f" /]
  56.                 [constraint firstAttribute= "bottom" secondItem= "mwt-p9-tRE" secondAttribute= "bottom" constant= "40" id= "yBq-He-Jv8" /]
  57.  [/constraints]
  58.  [/view]
  59.  [/objects]
  60.  [/document]

NSURLConnectionDelegateViewController.h

  1.  # import   @interface NSURLConnectionDelegateViewController : UIViewController
  2.  @property (strong, nonatomic) NSMutableData *mDataReceive;
  3.  @property (assign, nonatomic) NSUInteger totalDataLength; 
  4.   
  5.  @property (strong, nonatomic) IBOutlet UILabel *lblFileName;
  6.  @property (strong, nonatomic) IBOutlet UIProgressView *progVDownloadFile;
  7.  @property (strong, nonatomic) IBOutlet UILabel *lblMessage;
  8.  @property (strong, nonatomic) IBOutlet UIButton *btnDownloadFile; 
  9.   
  10.  @end  

NSURLConnectionDelegateViewController.m

  1.  # import   "NSURLConnectionDelegateViewController.h"  
  2.  # import   "UIButton+BeautifulButton.h"   
  3.   
  4.  @interface NSURLConnectionDelegateViewController ()
  5.  - ( void )layoutUI;
  6.  - (BOOL)isExistCacheInMemory:(NSURLRequest *)request;
  7.  - ( void )updateProgress;
  8.  @end   
  9.   
  10.  @implementation NSURLConnectionDelegateViewController 
  11.   
  12.  - ( void )viewDidLoad {
  13.  [ super viewDidLoad]; 
  14.       
  15.  [self layoutUI];
  16.  } 
  17.   
  18.  - ( void )didReceiveMemoryWarning {
  19.     [ super didReceiveMemoryWarning];
  20.  // Dispose of any resources that can be recreated.  
  21.  } 
  22.   
  23.  - ( void )layoutUI {
  24.     self.navigationItem.title = kTitleOfNSURLConnectionDelegate;
  25.     self.view.backgroundColor = [UIColor colorWithWhite: 0.95 alpha: 1.000 ]; 
  26.       
  27.     [_btnDownloadFile beautifulButton:nil];
  28.  } 
  29.   
  30.  - (BOOL)isExistCacheInMemory:(NSURLRequest *)request {
  31.  BOOL isExistCache = NO;
  32.     NSURLCache *cache = [NSURLCache sharedURLCache];
  33.     [cache setMemoryCapacity: 1024 * 1024 ]; //1M   
  34.       
  35.     NSCachedURLResponse *response = [cache cachedResponseForRequest:request];
  36.  if (response != nil) {
  37.  NSLog(@ "There is a response cache corresponding to the request in memory" );
  38.  isExistCache = YES;
  39.  }
  40.  return isExistCache;
  41.  } 
  42.   
  43.  - ( void )updateProgress {
  44.     NSUInteger receiveDataLength = _mDataReceive.length;
  45.  if (receiveDataLength == _totalDataLength) {
  46.  _lblMessage.text = @ "Download completed" ;
  47.         kApplication.networkActivityIndicatorVisible = NO;
  48.  } else {
  49.  _lblMessage.text = @ "Downloading..." ;
  50.         kApplication.networkActivityIndicatorVisible = YES;
  51.         _progVDownloadFile.progress = ( float )receiveDataLength / _totalDataLength;
  52.  }
  53.  } 
  54.   
  55.  - (IBAction)downloadFile:(id)sender {
  56.  /*
  57.  This example is more to help you understand the process of the proxy method receiving response data. It is impossible to use this method to download files in actual development. This download has a fatal problem: it cannot download large files. Because when the proxy method receives data, although it appears to read a part of the response data each time, in fact it only has one request and only receives one server response. It's just that when the response data is large, the system will repeatedly call the data receiving method, and each time it will take out a part of the read data and give it to the data receiving method. In this process, all the response data has already been obtained, but it is just handed over to the developer in batches. In this way, if you download a file of several GB, it is probably unrealistic to download it on a real machine, not to mention downloading it on a simulator.
  58.  When developing file downloads, whether we use proxy methods or static methods to execute requests and responses, we will request data in batches instead of all at once. Assuming a file is 1G, then as long as we request 1M of data each time, we can download it after 1024 requests. So how can we make the server return only 1M of data each time?
  59.  In network development, you can set a Range information in the request header file, which represents the size of the request data. Through this field, you can cooperate with the server to accurately control the data range of each server response. For example, specify bytes=0-1023, then parse the Range information on the server side and return the data between 0 and 1023 of the file (a total of 1024Bytes). In this way, as long as you control this header file information every time you send a request, you can make batch requests.
  60.  Of course, in order to keep the entire data intact, the data requested each time needs to be gradually appended until the entire file request is completed. But how do you know the size of the entire file? In fact, in this example, the entire file size is obtained through the header information. He requested the entire data, which makes no sense for segmented downloads. Fortunately, in WEB development, we have another request method "HEAD". Through this request, the server will only respond to the header information, and other data will not be returned to the client. In this way, the size of the entire data can also be obtained.
  61.  */   
  62.       
  63.       
  64.     NSString *fileURLStr = kFileURLStr;
  65.  //Encoding operation; the corresponding decoding operation is to use the stringByRemovingPercentEncoding method  
  66.     fileURLStr = [fileURLStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
  67.     NSURL *fileURL = [NSURL URLWithString:fileURLStr]; 
  68.       
  69.  /*Create request
  70.  cachePolicy: Cache policy
  71.  1. NSURLRequestUseProtocolCachePolicy protocol cache, judge whether the cache is valid according to the Cache-Control field in the response, if the cache is valid, use the cached data, otherwise re-request from the server
  72.  2. NSURLRequestReloadIgnoringLocalCacheData does not use cache and directly requests new data
  73.  3. NSURLRequestReloadIgnoringCacheData is equivalent to NSURLRequestReloadIgnoringLocalCacheData
  74.  4. NSURLRequestReturnCacheDataElseLoad directly uses cached data regardless of whether it is valid or not. If there is no cache, re-request
  75.  5. NSURLRequestReturnCacheDataDontLoad directly uses cached data regardless of whether it is valid or not, and fails if there is no cached data
  76.        
  77.  timeoutInterval: timeout setting (default 60s)
  78.  */  
  79.     NSURLRequest *request = [[NSURLRequest alloc] initWithURL:fileURL
  80.                                                   cachePolicy:NSURLRequestUseProtocolCachePolicy
  81.                                               timeoutInterval: 60.0 ];
  82.  if ([self isExistCacheInMemory:request]) {
  83.         request = [[NSURLRequest alloc] initWithURL:fileURL
  84.                                         cachePolicy:NSURLRequestReturnCacheDataDontLoad
  85.                                     timeoutInterval: 60.0 ];
  86.  } 
  87.       
  88.  //Create a connection, asynchronous operation  
  89.     NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request
  90.                                                                   delegate:self];
  91.  [connection start]; //Start the connection  
  92.  } 
  93.   
  94.  #pragma mark -NSURLConnectionDataDelegate
  95.  - (NSURLRequest *)connection:(NSURLConnection *)connection willSendRequest:(NSURLRequest *)request redirectResponse:(NSURLResponse *)response {
  96.  NSLog(@ "The request is about to be sent" ); 
  97.       
  98.  return request;
  99.  } 
  100.   
  101.  - ( void )connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
  102.  NSLog(@ "Response received" ); 
  103.       
  104.     _mDataReceive = [NSMutableData new ];
  105.     _progVDownloadFile.progress = 0.0 ; 
  106.       
  107.  //Get the total length of the entire response through the Content-Length in the response header  
  108.  /*
  109.  {
  110.  "Accept-Ranges" = bytes;
  111.      "Cache-Control" = "max-age=7776000";
  112.      "Content-Length" = 592441;
  113.      "Content-Type" = "application/x-zip-compressed";
  114.      Date = "Wed, 02 Sep 2015 13:17:01 GMT";
  115.      Etag = "\"d8f617371f9cd01:0\"";
  116.      "Last-Modified" = "Mon, 01 Jun 2015 03:58:27 GMT";
  117.      Server = "Microsoft-IIS/7.5";
  118.      "X-Powered-By" = "ASP.NET";
  119.  }
  120.  */  
  121.     NSDictionary *dicHeaderField = [(NSHTTPURLResponse *)response allHeaderFields];
  122.     _totalDataLength = [[dicHeaderField objectForKey:@ "Content-Length" ] integerValue];
  123.  } 
  124.   
  125.  - ( void )connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
  126.  NSLog(@ "Response data has been received, the data length is %lu bytes..." , (unsigned long )[data length]); 
  127.       
  128.  [_mDataReceive appendData:data]; //Continuously receive data  
  129.  [self updateProgress]; //Continuously update the progress bar  
  130.  } 
  131.   
  132.  - ( void )connectionDidFinishLoading:(NSURLConnection *)connection {
  133.  NSLog(@ "All response data has been received" ); 
  134.       
  135.     NSString *savePath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject];
  136.     savePath = [savePath stringByAppendingPathComponent:_lblFileName.text];
  137.     [_mDataReceive writeToFile:savePath atomically:YES];
  138.  } 
  139.   
  140.  - ( void )connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
  141.  //If the connection times out or the connection address is incorrect, an error may be reported  
  142.  NSLog(@ "Connection error, error message: %@" , error.localizedDescription); 
  143.       
  144.  _lblMessage.text = @ "Connection error" ;
  145.  } 
  146.   
  147.  @end  

NSURLConnectionDelegateViewController.xib

  1.  [?xml version= "1.0" encoding= "UTF-8" standalone= "no" ?]
  2.  [document type= "com.apple.InterfaceBuilder3.CocoaTouch.XIB" version= "3.0" toolsVersion= "7706" systemVersion= "14E46" targetRuntime= "iOS.CocoaTouch" propertyAccessControl= "none" useAutolayout= "YES" useTraitCollections= "YES" ]
  3.  [dependencies]
  4.         [deployment identifier= "iOS" /]
  5.         [plugIn identifier= "com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version= "7703" /]
  6.  [/dependencies]
  7.  [objects]
  8.         [placeholder placeholderIdentifier= "IBFilesOwner" id= "-1" userLabel= "File's Owner" customClass= "NSURLConnectionDelegateViewController" ]
  9.  [connections]
  10.                 [outlet property= "btnDownloadFile" destination= "mwt-p9-tRE" id= "ZVc-6S-ES3" /]
  11.                 [outlet property= "lblFileName" destination= "dlB-Qn-eOO" id= "vJk-jh-Y2c" /]
  12.                 [outlet property= "lblMessage" destination= "qlQ-nM-BXU" id= "tRe-SR-AQE" /]
  13.                 [outlet property= "progVDownloadFile" destination= "Me3-m2-iC4" id= "PtK-m7-j5N" /]
  14.                 [outlet property= "view" destination= "i5M-Pr-FkT" id= "sfx-zR-JGt" /]
  15.  [/connections]
  16.  [/placeholder]
  17.         [placeholder placeholderIdentifier= "IBFirstResponder" id= "-2" customClass= "UIResponder" /]
  18.         [view clearsContextBeforeDrawing= "NO" contentMode= "scaleToFill" id= "i5M-Pr-FkT" ]
  19.             [rect key= "frame" x= "0.0" y= "0.0" width= "600" height= "600" /]
  20.             [autoresizingMask key= "autoresizingMask" widthSizable= "YES" heightSizable= "YES" /]
  21.  [subviews]
  22.                 [label opaque= "NO" userInteractionEnabled= "NO" contentMode= "left" horizontalHuggingPriority= "251" verticalHuggingPriority= "251" text= "metro_demo uses Highcharts to implement chart display.zip" lineBreakMode= "tailTruncation" baselineAdjustment= "alignBaselines" adjustsFontSizeToFit= "NO" translatesAutoresizingMaskIntoConstraints= "NO" id= "dlB-Qn-eOO" ]
  23.                     [rect key= "frame" x= "145" y= "104" width= "309.5" height= "18" /]
  24.                     [fontDescription key= "fontDescription" type= "boldSystem" pointSize= "15" /]
  25.                     [color key= "textColor" cocoaTouchSystemColor= "darkTextColor" /]
  26.                     [nil key= "highlightedColor" /]
  27.  [/label]
  28.                 [button opaque= "NO" contentMode= "scaleToFill" contentHorizontalAlignment= "center" contentVerticalAlignment= "center" buttonType= "roundedRect" lineBreakMode= "middleTruncation" translatesAutoresizingMaskIntoConstraints= "NO" id= "mwt-p9-tRE" ]
  29.                     [rect key= "frame" x= "250" y= "520" width= "100" height= "40" /]
  30.                     [constraints]
  31.                         [constraint firstAttribute= "width" constant= "100" id= "I5D-tA-ffH" /]
  32.                         [constraint firstAttribute= "height" constant= "40" id= "Y8C-D4-IVr" /]
  33.                     [/constraints]
  34.  [state key= "normal" title= "Download" ]
  35.                         [color key= "titleShadowColor" white= "0.5" alpha= "1" colorSpace= "calibratedWhite" /]
  36.  [/state]
  37.                     [connections]
  38.                         [action selector= "downloadFile:" destination= "-1" eventType= "touchUpInside" id= "iGc-6N-bsZ" /]
  39.                     [/connections]
  40.  [/button]
  41.                 [progressView opaque= "NO" contentMode= "scaleToFill" verticalHuggingPriority= "750" translatesAutoresizingMaskIntoConstraints= "NO" id= "Me3-m2-iC4" ]
  42.                     [rect key= "frame" x= "145" y= "160" width= "310" height= "2" /]
  43.                     [constraints]
  44.                         [constraint firstAttribute= "height" constant= "2" id= "I50-Zx-DwT" /]
  45.                         [constraint firstAttribute= "width" constant= "310" id= "wdS-eD-Tkc" /]
  46.                     [/constraints]
  47.                 [/progressView]
  48.                 [label opaque= "NO" userInteractionEnabled= "NO" contentMode= "left" horizontalHuggingPriority= "251" verticalHuggingPriority= "251" text= "Label" lineBreakMode= "tailTruncation" baselineAdjustment= "alignBaselines" adjustsFontSizeToFit= "NO" translatesAutoresizingMaskIntoConstraints= "NO" id= "qlQ-nM-BXU" ]
  49.                     [rect key= "frame" x= "145" y= "180" width= "37.5" height= "18" /]
  50.                     [fontDescription key= "fontDescription" type= "system" pointSize= "15" /]
  51.                     [color key= "textColor" red= "0.0" green= "0.50196081399917603" blue= "1" alpha= "1" colorSpace= "calibratedRGB" /]
  52.                     [nil key= "highlightedColor" /]
  53.                     [userDefinedRuntimeAttributes]
  54.                         [userDefinedRuntimeAttribute type= "string" keyPath= "text" value= "" /]
  55.                     [/userDefinedRuntimeAttributes]
  56.  [/label]
  57.  [/subviews]
  58.             [color key= "backgroundColor" white= "1" alpha= "1" colorSpace= "custom" customColorSpace= "calibratedWhite" /]
  59.  [constraints]
  60.                 [constraint firstAttribute= "centerX" secondItem= "Me3-m2-iC4" secondAttribute= "centerX" id= "Ya8-bM-TaA" /]
  61.                 [constraint firstItem= "Me3-m2-iC4" firstAttribute= "top" secondItem= "i5M-Pr-FkT" secondAttribute= "top" constant= "160" id= "bOY-B5-is2" /]
  62.                 [constraint firstAttribute= "centerX" secondItem= "dlB-Qn-eOO" secondAttribute= "centerX" id= "gNK-NO-rth" /]
  63.                 [constraint firstItem= "dlB-Qn-eOO" firstAttribute= "top" secondItem= "i5M-Pr-FkT" secondAttribute= "top" constant= "104" id= "hwU-O2-Fed" /]
  64.                 [constraint firstItem= "qlQ-nM-BXU" firstAttribute= "leading" secondItem= "Me3-m2-iC4" secondAttribute= "leading" id= "lus-oi-9SA" /]
  65.                 [constraint firstAttribute= "centerX" secondItem= "mwt-p9-tRE" secondAttribute= "centerX" id= "teN-3t-8Gc" /]
  66.                 [constraint firstItem= "qlQ-nM-BXU" firstAttribute= "top" secondItem= "i5M-Pr-FkT" secondAttribute= "top" constant= "180" id= "w3g-ej-P18" /]
  67.                 [constraint firstAttribute= "bottom" secondItem= "mwt-p9-tRE" secondAttribute= "bottom" constant= "40" id= "yBq-He-Jv8" /]
  68.  [/constraints]
  69.  [/view]
  70.  [/objects]
  71.  [/document]

NSURLSessionViewController.h

  1.  # import   @interface NSURLSessionViewController : UIViewController
  2.  @property (strong, nonatomic) IBOutlet UILabel *lblFileName;
  3.  @property (strong, nonatomic) IBOutlet UILabel *lblMessage;
  4.  @property (strong, nonatomic) IBOutlet UIButton *btnDownloadFile; 
  5.   
  6.  @end  

NSURLSessionViewController.m

  1.  # import   "NSURLSessionViewController.h"  
  2.  # import   "UIButton+BeautifulButton.h"   
  3.   
  4.  @interface NSURLSessionViewController ()
  5.  - ( void )layoutUI;
  6.  @end   
  7.   
  8.  @implementation NSURLSessionViewController 
  9.   
  10.  - ( void )viewDidLoad {
  11.  [ super viewDidLoad]; 
  12.       
  13.  [self layoutUI];
  14.  } 
  15.   
  16.  - ( void )didReceiveMemoryWarning {
  17.     [ super didReceiveMemoryWarning];
  18.  // Dispose of any resources that can be recreated.  
  19.  } 
  20.   
  21.  - ( void )layoutUI {
  22.     self.navigationItem.title = kTitleOfNSURLSession;
  23.     self.view.backgroundColor = [UIColor colorWithWhite: 0.95 alpha: 1.000 ]; 
  24.       
  25.     [_btnDownloadFile beautifulButton:nil];
  26.  } 
  27.   
  28.  - (IBAction)downloadFile:(id)sender {
  29.  _lblMessage.text = @ "Downloading..." ; 
  30.       
  31.     NSString *fileURLStr = kFileURLStr;
  32.  //Encoding operation; the corresponding decoding operation is to use the stringByRemovingPercentEncoding method  
  33.     fileURLStr = [fileURLStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
  34.     NSURL *fileURL = [NSURL URLWithString:fileURLStr]; 
  35.       
  36.  //Create request  
  37.     NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:fileURL]; 
  38.       
  39.  //Create a session (a global session is used here)  
  40.     NSURLSession *session = [NSURLSession sharedSession]; 
  41.       
  42.  //Create a download task and start it; execute in a non-main thread  
  43.     NSURLSessionDownloadTask *downloadTask = [session downloadTaskWithRequest:request completionHandler:^(NSURL *location, NSURLResponse *response, NSError *error) {
  44.  __block void (^updateUI)(); //Declare the code block used for the main thread to update the UI   
  45.           
  46.  if (!error) {
  47.  NSLog(@ "Temporary save path after downloading: %@" , location); 
  48.               
  49.             NSString *savePath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject];
  50.             savePath = [savePath stringByAppendingPathComponent:_lblFileName.text];
  51.             NSURL *saveURL = [NSURL fileURLWithPath:savePath];
  52.             NSError *saveError;
  53.             NSFileManager *fileManager = [NSFileManager defaultManager];
  54.  // Check if there is an old target file, if so remove it first to avoid the problem of being unable to copy  
  55.  if ([fileManager fileExistsAtPath:savePath]) {
  56.                 [fileManager removeItemAtPath:savePath error:&saveError];
  57.  if (saveError) {
  58.  NSLog(@ "Failed to remove the old target file, error message: %@" , saveError.localizedDescription); 
  59.                       
  60.                     updateUI = ^ {
  61.  _lblMessage.text = @ "Download failed" ;
  62.  };
  63.  }
  64.  }
  65.  if (!saveError) {
  66.  //Copy the source file to the target file. If the target file exists, an error will be thrown to the object instance pointed to by the error parameter.  
  67.  //Method 1 (path cannot have file:// prefix)  
  68.  // [fileManager copyItemAtPath:[location path]  
  69.  // toPath:savePath  
  70.  // error:&saveError];   
  71.                   
  72.  //Method 2  
  73.                 [fileManager copyItemAtURL:location
  74.                                      toURL:saveURL
  75.                                      error:&saveError]; 
  76.                   
  77.  if (!saveError) {
  78.  NSLog(@ "Save successfully" ); 
  79.                       
  80.                     updateUI = ^ {
  81.  _lblMessage.text = @ "Download completed" ;
  82.  };
  83.  } else {
  84.  NSLog(@ "Save failed, error message: %@" , saveError.localizedDescription); 
  85.                       
  86.                     updateUI = ^ {
  87.  _lblMessage.text = @ "Download failed" ;
  88.  };
  89.  }
  90.  } 
  91.               
  92.  } else {
  93.  NSLog(@ "Download failed, error message: %@" , error.localizedDescription); 
  94.               
  95.  updateUI = ^ {
  96.  _lblMessage.text = @ "Download failed" ;
  97.  };
  98.  } 
  99.           
  100.  dispatch_async(dispatch_get_main_queue(), updateUI); //Use the main queue asynchronous method (main thread) to execute the code block that updates the UI  
  101.  }];
  102.  [downloadTask resume]; //Resume thread and start task  
  103.  } 
  104.   
  105.  @end  

#p#

NSURLSessionViewController.xib

  1.  [?xml version= "1.0" encoding= "UTF-8" standalone= "no" ?]
  2.  [document type= "com.apple.InterfaceBuilder3.CocoaTouch.XIB" version= "3.0" toolsVersion= "7706" systemVersion= "14E46" targetRuntime= "iOS.CocoaTouch" propertyAccessControl= "none" useAutolayout= "YES" useTraitCollections= "YES" ]
  3.  [dependencies]
  4.         [deployment identifier= "iOS" /]
  5.         [plugIn identifier= "com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version= "7703" /]
  6.  [/dependencies]
  7.  [objects]
  8.         [placeholder placeholderIdentifier= "IBFilesOwner" id= "-1" userLabel= "File's Owner" customClass= "NSURLSessionViewController" ]
  9.  [connections]
  10.                 [outlet property= "btnDownloadFile" destination= "mwt-p9-tRE" id= "ZVc-6S-ES3" /]
  11.                 [outlet property= "lblFileName" destination= "dlB-Qn-eOO" id= "NdS-9n-7KX" /]
  12.                 [outlet property= "lblMessage" destination= "qlQ-nM-BXU" id= "tRe-SR-AQE" /]
  13.                 [outlet property= "view" destination= "i5M-Pr-FkT" id= "sfx-zR-JGt" /]
  14.  [/connections]
  15.  [/placeholder]
  16.         [placeholder placeholderIdentifier= "IBFirstResponder" id= "-2" customClass= "UIResponder" /]
  17.         [view clearsContextBeforeDrawing= "NO" contentMode= "scaleToFill" id= "i5M-Pr-FkT" ]
  18.             [rect key= "frame" x= "0.0" y= "0.0" width= "600" height= "600" /]
  19.             [autoresizingMask key= "autoresizingMask" widthSizable= "YES" heightSizable= "YES" /]
  20.  [subviews]
  21.                 [label opaque= "NO" userInteractionEnabled= "NO" contentMode= "left" horizontalHuggingPriority= "251" verticalHuggingPriority= "251" text= "metro_demo uses Highcharts to implement chart display.zip" lineBreakMode= "tailTruncation" baselineAdjustment= "alignBaselines" adjustsFontSizeToFit= "NO" translatesAutoresizingMaskIntoConstraints= "NO" id= "dlB-Qn-eOO" ]
  22.                     [rect key= "frame" x= "145" y= "104" width= "309.5" height= "18" /]
  23.                     [fontDescription key= "fontDescription" type= "boldSystem" pointSize= "15" /]
  24.                     [color key= "textColor" cocoaTouchSystemColor= "darkTextColor" /]
  25.                     [nil key= "highlightedColor" /]
  26.  [/label]
  27.                 [button opaque= "NO" contentMode= "scaleToFill" contentHorizontalAlignment= "center" contentVerticalAlignment= "center" buttonType= "roundedRect" lineBreakMode= "middleTruncation" translatesAutoresizingMaskIntoConstraints= "NO" id= "mwt-p9-tRE" ]
  28.                     [rect key= "frame" x= "250" y= "520" width= "100" height= "40" /]
  29.                     [constraints]
  30.                         [constraint firstAttribute= "width" constant= "100" id= "I5D-tA-ffH" /]
  31.                         [constraint firstAttribute= "height" constant= "40" id= "Y8C-D4-IVr" /]
  32.                     [/constraints]
  33.  [state key= "normal" title= "Download" ]
  34.                         [color key= "titleShadowColor" white= "0.5" alpha= "1" colorSpace= "calibratedWhite" /]
  35.  [/state]
  36.                     [connections]
  37.                         [action selector= "downloadFile:" destination= "-1" eventType= "touchUpInside" id= "MK4-Yk-IOk" /]
  38.                     [/connections]
  39.  [/button]
  40.                 [label opaque= "NO" userInteractionEnabled= "NO" contentMode= "left" horizontalHuggingPriority= "251" verticalHuggingPriority= "251" text= "Label" lineBreakMode= "tailTruncation" baselineAdjustment= "alignBaselines" adjustsFontSizeToFit= "NO" translatesAutoresizingMaskIntoConstraints= "NO" id= "qlQ-nM-BXU" ]
  41.                     [rect key= "frame" x= "145" y= "140" width= "37.5" height= "18" /]
  42.                     [fontDescription key= "fontDescription" type= "system" pointSize= "15" /]
  43.                     [color key= "textColor" red= "0.0" green= "0.50196081399917603" blue= "1" alpha= "1" colorSpace= "calibratedRGB" /]
  44.                     [nil key= "highlightedColor" /]
  45.                     [userDefinedRuntimeAttributes]
  46.                         [userDefinedRuntimeAttribute type= "string" keyPath= "text" value= "" /]
  47.                     [/userDefinedRuntimeAttributes]
  48.  [/label]
  49.  [/subviews]
  50.             [color key= "backgroundColor" white= "1" alpha= "1" colorSpace= "custom" customColorSpace= "calibratedWhite" /]
  51.  [constraints]
  52.                 [constraint firstAttribute= "centerX" secondItem= "dlB-Qn-eOO" secondAttribute= "centerX" id= "gNK-NO-rth" /]
  53.                 [constraint firstItem= "dlB-Qn-eOO" firstAttribute= "top" secondItem= "i5M-Pr-FkT" secondAttribute= "top" constant= "104" id= "hwU-O2-Fed" /]
  54.                 [constraint firstAttribute= "centerX" secondItem= "mwt-p9-tRE" secondAttribute= "centerX" id= "teN-3t-8Gc" /]
  55.                 [constraint firstItem= "qlQ-nM-BXU" firstAttribute= "top" secondItem= "i5M-Pr-FkT" secondAttribute= "top" constant= "140" id= "w3g-ej-P18" /]
  56.                 [constraint firstItem= "dlB-Qn-eOO" firstAttribute= "leading" secondItem= "qlQ-nM-BXU" secondAttribute= "leading" constant= "0.5" id= "wMU-pU-z9f" /]
  57.                 [constraint firstAttribute= "bottom" secondItem= "mwt-p9-tRE" secondAttribute= "bottom" constant= "40" id= "yBq-He-Jv8" /]
  58.  [/constraints]
  59.  [/view]
  60.  [/objects]
  61.  [/document]

NSURLSessionDelegateViewController.h

  1.  # import   @interface NSURLSessionDelegateViewController : UIViewController @property (strong, nonatomic) NSURLSessionDownloadTask *downloadTask; 
  2.   
  3.  @property (strong, nonatomic) IBOutlet UILabel *lblFileName;
  4.  @property (strong, nonatomic) IBOutlet UIProgressView *progVDownloadFile;
  5.  @property (strong, nonatomic) IBOutlet UILabel *lblMessage;
  6.  @property (strong, nonatomic) IBOutlet UIButton *btnDownloadFile;
  7.  @property (strong, nonatomic) IBOutlet UIButton *btnCancel;
  8.  @property (strong, nonatomic) IBOutlet UIButton *btnSuspend;
  9.  @property (strong, nonatomic) IBOutlet UIButton *btnResume; 
  10.   
  11.  @end  

NSURLSessionDelegateViewController.m

  1.  # import   "NSURLSessionDelegateViewController.h"  
  2.  # import   "UIButton+BeautifulButton.h"   
  3.   
  4.  @interface NSURLSessionDelegateViewController ()
  5.  - ( void )layoutUI;
  6.  - (NSURLSession *)defaultSession;
  7.  - (NSURLSession *)backgroundSession;
  8.  - ( void )updateProgress:(int64_t)receiveDataLength totalDataLength:(int64_t)totalDataLength;
  9.  @end   
  10.   
  11.  @implementation NSURLSessionDelegateViewController 
  12.   
  13.  - ( void )viewDidLoad {
  14.  [ super viewDidLoad]; 
  15.       
  16.  [self layoutUI];
  17.  } 
  18.   
  19.  - ( void )didReceiveMemoryWarning {
  20.     [ super didReceiveMemoryWarning];
  21.  // Dispose of any resources that can be recreated.  
  22.  } 
  23.   
  24.  - ( void )layoutUI {
  25.     self.navigationItem.title = kTitleOfNSURLSessionDelegate;
  26.     self.view.backgroundColor = [UIColor colorWithWhite: 0.95 alpha: 1.000 ]; 
  27.       
  28.     [_btnDownloadFile beautifulButton:nil];
  29.     [_btnCancel beautifulButton:[UIColor redColor]];
  30.     [_btnSuspend beautifulButton:[UIColor purpleColor]];
  31.     [_btnResume beautifulButton:[UIColor orangeColor]];
  32.  } 
  33.   
  34.  - (NSURLSession *)defaultSession {
  35.  /*
  36.  NSURLSession supports three types of process sessions:
  37.  1. defaultSessionConfiguration: In-process session (default session), using the hard disk to cache data.
  38.  2. ephemeralSessionConfiguration: A temporary in-process session (memory), which will not store cookies and caches locally, but will only be placed in memory. The data will also disappear when the application exits.
  39.  3. BackgroundSessionConfiguration: Background Session. Compared with the default session, this session will open a thread in the background for network data processing.
  40.  */   
  41.   
  42.  //Create session configuration "In-process session"  
  43.     NSURLSessionConfiguration *sessionConfiguration = [NSURLSessionConfiguration defaultSessionConfiguration];
  44.  sessionConfiguration.timeoutIntervalForRequest = 60.0 ; //Request timeout time; default is 60 seconds  
  45.  sessionConfiguration.allowsCellularAccess = YES; // Whether to allow cellular network access (2G/3G/4G)  
  46.  sessionConfiguration.HTTPMaximumConnectionsPerHost = 4 ; //Limit the maximum number of connections per time; the default value in iOS is 4   
  47.       
  48.  //Create a session  
  49.     NSURLSession *session = [NSURLSession sessionWithConfiguration:sessionConfiguration
  50.                                                           delegate:self
  51.                                                      delegateQueue:nil];
  52.  return session;
  53.  } 
  54.   
  55.  - (NSURLSession *)backgroundSession {
  56.  static NSURLSession *session;
  57.  static dispatch_once_t onceToken;
  58.  dispatch_once(&onceToken, ^{ //Only execute once during the application life cycle; guarantees that there is only one "backend session"  
  59.  //Create a session to configure "backend session"  
  60.         NSURLSessionConfiguration *sessionConfiguration = [NSURLSessionConfiguration backgroundSessionConfigurationWithIdentifier:@ "KMDownloadFile.NSURLSessionDelegateViewController" ];
  61.  sessionConfiguration.timeoutIntervalForRequest = 60.0 ; //Request timeout time; default is 60 seconds  
  62.  sessionConfiguration.allowsCellularAccess = YES; // Whether to allow cellular network access (2G/3G/4G)  
  63.  sessionConfiguration.HTTPMaximumConnectionsPerHost = 4 ; //Limit the maximum number of connections per time; the default value in iOS is 4  
  64.  sessionConfiguration.discretionary = YES; // Whether to automatically select the best network access, it is only valid for "backend sessions"   
  65.           
  66.  //Create a session  
  67.         session = [NSURLSession sessionWithConfiguration:sessionConfiguration
  68.                                                 delegate:self
  69.                                            delegateQueue:nil];
  70.  });
  71.  return session;
  72.  } 
  73.   
  74.  - ( void )updateProgress:(int64_t)receiveDataLength totalDataLength:(int64_t)totalDataLength; {
  75.  dispatch_async(dispatch_get_main_queue(), ^{ //Use the main queue asynchronous method (main thread) to perform update UI operations  
  76.  if (receiveDataLength == totalDataLength) {
  77.  _lblMessage.text = @ "Download Completed" ;
  78.             kApplication.networkActivityIndicatorVisible = NO;
  79.  } else {
  80.  _lblMessage.text = @ "Download..." ;
  81.             kApplication.networkActivityIndicatorVisible = YES;
  82.             _progVDownloadFile.progress = ( float )receiveDataLength / totalDataLength;
  83.  }
  84.  });
  85.  } 
  86.   
  87.  - (IBAction)downloadFile:(id)sender {
  88.     NSString *fileURLStr = kFileURLStr;
  89.  //Encoding operation; the corresponding decoding operation is to use the stringByRemovingPercentEncoding method  
  90.     fileURLStr = [fileURLStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
  91.     NSURL *fileURL = [NSURL URLWithString:fileURLStr]; 
  92.       
  93.  //Create a request  
  94.     NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:fileURL]; 
  95.       
  96.  //Create a session "in-process session"; if you want to use "background session", use the custom [self backgroundSession] method  
  97.     NSURLSession *session = [self defaultSession]; 
  98.       
  99.  //Create a download task and start it; execute in a non-main thread  
  100.     _downloadTask = [session downloadTaskWithRequest:request];
  101.  [_downloadTask resume]; 
  102.       
  103.  /*
  104.  Session task status
  105.      typedef NS_ENUM(NSInteger, NSURLSessionTaskState) {
  106.  NSURLSessionTaskStateRunning = 0, //Execution is underway
  107.  NSURLSessionTaskStateSuspended = 1, //Hanged
  108.  NSURLSessionTaskStateCanceling = 2, //Canceling
  109.  NSURLSessionTaskStateCompleted = 3, //Completed
  110.      } NS_ENUM_AVAILABLE(NSURLSESSION_AVAILABLE, 7_0);
  111.  */  
  112.  } 
  113.   
  114.  - (IBAction)cancel:(id)sender {
  115.  [_downloadTask cancel];
  116.  } 
  117.   
  118.  - (IBAction)suspend:(id)sender {
  119.  [_downloadTask suspend];
  120.     kApplication.networkActivityIndicatorVisible = NO;
  121.  } 
  122.   
  123.  - (IBAction)resume:(id)sender {
  124.  [_downloadTask resume];
  125.  } 
  126.   
  127.  #pragma mark - NSURLSessionDownloadDelegate
  128.  - ( void )URLSession:(NSURLSession *)session downloadTask:(NSURLSessionDownloadTask *)downloadTask didWriteData:(int64_t)bytesWritten totalBytesWritten:(int64_t)totalBytesWritten totalBytesExpectedToWrite:(int64_t)totalBytesExpectedToWrite {
  129.  NSLog(@ "Response data has been received, the data length is %lld bytes..." , totalBytesWritten); 
  130.       
  131.     [self updateProgress:totalBytesWritten totalDataLength:totalBytesExpectedToWrite];
  132.  } 
  133.   
  134.  - ( void )URLSession:(NSURLSession *)session downloadTask:(NSURLSessionDownloadTask *)downloadTask didFinishDownloadingToURL:(NSURL *)location {
  135.  //The download file will be temporarily saved. Under normal processes, the system will eventually automatically clear the temporary file; the save path directory varies according to the session type:  
  136.  //"In-process session (default session)" and "temporary in-process session (memory)". The path directory is: /tmp, which can be obtained through the NSTemporaryDirectory() method.  
  137.  //"Background Session", the path directory is: /Library/Caches/com.apple.nurlsessiond/Downloads/com.kenmu.KMDownloadFile  
  138.  NSLog(@ "All response data has been received, temporary save path after download: %@" , location); 
  139.       
  140.  __block void (^updateUI)(); //Declare the code block used for the main thread to update the UI   
  141.       
  142.     NSString *savePath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject];
  143.     savePath = [savePath stringByAppendingPathComponent:_lblFileName.text];
  144.     NSURL *saveURL = [NSURL fileURLWithPath:savePath];
  145.  NSError *saveError;
  146.     NSFileManager *fileManager = [NSFileManager defaultManager];
  147.  //Judge whether the old target file exists, and remove it first if it exists; avoid the problem of being unable to copy  
  148.  if ([fileManager fileExistsAtPath:savePath]) {
  149.         [fileManager removeItemAtPath:savePath error:&saveError];
  150.  if (saveError) {
  151.  NSLog(@ "Failed to remove the old target file, error message: %@" , saveError.localizedDescription); 
  152.               
  153.  updateUI = ^ {
  154.  _lblMessage.text = @ "Download failed" ;
  155.  };
  156.  }
  157.  }
  158.  if (!saveError) {
  159.  //Copy the source file to the target file. When the target file exists, an error will be thrown to the object instance pointed to by the error parameter.  
  160.  //Method 1 (path cannot have file:// prefix)  
  161.  //                [fileManager copyItemAtPath:[location path]  
  162.  //                                     toPath:savePath  
  163.  //                                      error:&saveError];   
  164.           
  165.  //Method 2  
  166.         [fileManager copyItemAtURL:location
  167.                              toURL:saveURL
  168.                              error:&saveError]; 
  169.           
  170.  if (!saveError) {
  171.  NSLog(@ "Save successfully" ); 
  172.               
  173.  updateUI = ^ {
  174.  _lblMessage.text = @ "Download Completed" ;
  175.  };
  176.  } else {
  177.  NSLog(@ "Save failed, error message: %@" , saveError.localizedDescription); 
  178.               
  179.  updateUI = ^ {
  180.  _lblMessage.text = @ "Download failed" ;
  181.  };
  182.  }
  183.  } 
  184.       
  185.  dispatch_async(dispatch_get_main_queue(), updateUI); //Use the main queue asynchronous method (main thread) to perform the code block that updates the UI  
  186.  } 
  187.   
  188.  - ( void )URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error {
  189.  NSLog(@ "Whether the download is successful or failed, it will be executed once in the end" ); 
  190.       
  191.  if (error) {
  192.         NSString *desc = error.localizedDescription;
  193.  NSLog(@ "Download failed, error message: %@" , desc); 
  194.           
  195.  dispatch_async(dispatch_get_main_queue(), ^{ //Use the main queue asynchronous method (main thread) to perform update UI operations  
  196.  _lblMessage.text = [desc isEqualToString:@ "cancelled" ] ? @ "Download Cancel" : @ "Download failed" ;
  197.             kApplication.networkActivityIndicatorVisible = NO;
  198.             _progVDownloadFile.progress = 0.0 ;
  199.  });
  200.  }
  201.  } 
  202.   
  203.  @end  

NSURLSessionDelegateViewController.xib

  1.  [?xml version= "1.0" encoding= "UTF-8" standalone= "no" ?]
  2.  [document type= "com.apple.InterfaceBuilder3.CocoaTouch.XIB" version= "3.0" toolsVersion= "7706" systemVersion= "14E46" targetRuntime= "iOS.CocoaTouch" propertyAccessControl= "none" useAutolayout= "YES" useTraitCollections= "YES" ]
  3.  [dependencies]
  4.         [deployment identifier= "iOS" /]
  5.         [plugIn identifier= "com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version= "7703" /]
  6.  [/dependencies]
  7.  [objects]
  8.         [placeholder placeholderIdentifier= "IBFilesOwner" id= "-1" userLabel= "File's Owner" customClass= "NSURLSessionDelegateViewController" ]
  9.  [connections]
  10.                 [outlet property= "btnCancel" destination= "yMY-kU-iKL" id= "QHP-ls-q8P" /]
  11.                 [outlet property= "btnDownloadFile" destination= "mwt-p9-tRE" id= "ZVc-6S-ES3" /]
  12.                 [outlet property= "btnResume" destination= "YSM-n6-UM4" id= "RyL-54-rFB" /]
  13.                 [outlet property= "btnSuspend" destination= "5kz-pB-9nK" id= "1Jj-zV-DXM" /]
  14.                 [outlet property= "lblFileName" destination= "dlB-Qn-eOO" id= "vJk-jh-Y2c" /]
  15.                 [outlet property= "lblMessage" destination= "qlQ-nM-BXU" id= "tRe-SR-AQE" /]
  16.                 [outlet property= "progVDownloadFile" destination= "Me3-m2-iC4" id= "PtK-m7-j5N" /]
  17.                 [outlet property= "view" destination= "i5M-Pr-FkT" id= "sfx-zR-JGt" /]
  18.  [/connections]
  19.  [/placeholder]
  20.         [placeholder placeholderIdentifier= "IBFirstResponder" id= "-2" customClass= "UIResponder" /]
  21.         [view clearsContextBeforeDrawing= "NO" contentMode= "scaleToFill" id= "i5M-Pr-FkT" ]
  22.             [rect key= "frame" x= "0.0" y= "0.0" width= "600" height= "600" /]
  23.             [autoresizingMask key= "autoresizingMask" widthSizable= "YES" heightSizable= "YES" /]
  24.  [subviews]
  25.                 [label opaque= "NO" userInteractionEnabled= "NO" contentMode= "left" horizontalHuggingPriority= "251" verticalHuggingPriority= "251" text= "metro_demo使用Highcharts实现图表展示.zip" lineBreakMode= "tailTruncation" baselineAdjustment= "alignBaselines" adjustsFontSizeToFit= "NO" translatesAutoresizingMaskIntoConstraints= "NO" id= "dlB-Qn-eOO" ]
  26.                     [rect key= "frame" x= "145" y= "104" width= "309.5" height= "18" /]
  27.                     [fontDescription key= "fontDescription" type= "boldSystem" pointSize= "15" /]
  28.                     [color key= "textColor" cocoaTouchSystemColor= "darkTextColor" /]
  29.                     [nil key= "highlightedColor" /]
  30.  [/label]
  31.                 [button opaque= "NO" contentMode= "scaleToFill" contentHorizontalAlignment= "center" contentVerticalAlignment= "center" buttonType= "roundedRect" lineBreakMode= "middleTruncation" translatesAutoresizingMaskIntoConstraints= "NO" id= "mwt-p9-tRE" ]
  32.                     [rect key= "frame" x= "145" y= "520" width= "70" height= "40" /]
  33.                     [constraints]
  34.                         [constraint firstAttribute= "width" constant= "70" id= "I5D-tA-ffH" /]
  35.                         [constraint firstAttribute= "height" constant= "40" id= "Y8C-D4-IVr" /]
  36.                     [/constraints]
  37.  [state key= "normal" title= "Download" ]
  38.                         [color key= "titleShadowColor" white= "0.5" alpha= "1" colorSpace= "calibratedWhite" /]
  39.  [/state]
  40.                     [connections]
  41.                         [action selector= "downloadFile:" destination= "-1" eventType= "touchUpInside" id= "iGc-6N-bsZ" /]
  42.                     [/connections]
  43.  [/button]
  44.                 [progressView opaque= "NO" contentMode= "scaleToFill" verticalHuggingPriority= "750" translatesAutoresizingMaskIntoConstraints= "NO" id= "Me3-m2-iC4" ]
  45.                     [rect key= "frame" x= "145" y= "160" width= "310" height= "2" /]
  46.                     [constraints]
  47.                         [constraint firstAttribute= "height" constant= "2" id= "I50-Zx-DwT" /]
  48.                         [constraint firstAttribute= "width" constant= "310" id= "wdS-eD-Tkc" /]
  49.                     [/constraints]
  50.                 [/progressView]
  51.                 [label opaque= "NO" userInteractionEnabled= "NO" contentMode= "left" horizontalHuggingPriority= "251" verticalHuggingPriority= "251" text= "Label" lineBreakMode= "tailTruncation" baselineAdjustment= "alignBaselines" adjustsFontSizeToFit= "NO" translatesAutoresizingMaskIntoConstraints= "NO" id= "qlQ-nM-BXU" ]
  52.                     [rect key= "frame" x= "145" y= "180" width= "37.5" height= "18" /]
  53.                     [fontDescription key= "fontDescription" type= "system" pointSize= "15" /]
  54.                     [color key= "textColor" red= "0.0" green= "0.50196081399917603" blue= "1" alpha= "1" colorSpace= "calibratedRGB" /]
  55.                     [nil key= "highlightedColor" /]
  56.                     [userDefinedRuntimeAttributes]
  57.                         [userDefinedRuntimeAttribute type= "string" keyPath= "text" value= "" /]
  58.                     [/userDefinedRuntimeAttributes]
  59.  [/label]
  60.                 [button opaque= "NO" contentMode= "scaleToFill" contentHorizontalAlignment= "center" contentVerticalAlignment= "center" buttonType= "roundedRect" lineBreakMode= "middleTruncation" translatesAutoresizingMaskIntoConstraints= "NO" id= "5kz-pB-9nK" ]
  61.                     [rect key= "frame" x= "305" y= "520" width= "70" height= "40" /]
  62.                     [constraints]
  63.                         [constraint firstAttribute= "width" constant= "70" id= "IOm-ve-DPG" /]
  64.                         [constraint firstAttribute= "height" constant= "40" id= "Kwn-EW-gDl" /]
  65.                     [/constraints]
  66.  [state key= "normal" title= "hang" ]
  67.                         [color key= "titleShadowColor" white= "0.5" alpha= "1" colorSpace= "calibratedWhite" /]
  68.  [/state]
  69.                     [connections]
  70.                         [action selector= "suspend:" destination= "-1" eventType= "touchUpInside" id= "O6j-t2-7Lv" /]
  71.                     [/connections]
  72.  [/button]
  73.                 [button opaque= "NO" contentMode= "scaleToFill" contentHorizontalAlignment= "center" contentVerticalAlignment= "center" buttonType= "roundedRect" lineBreakMode= "middleTruncation" translatesAutoresizingMaskIntoConstraints= "NO" id= "YSM-n6-UM4" ]
  74.                     [rect key= "frame" x= "385" y= "520" width= "70" height= "40" /]
  75.                     [constraints]
  76.                         [constraint firstAttribute= "width" constant= "70" id= "LhS-5f-cG4" /]
  77.                         [constraint firstAttribute= "height" constant= "40" id= "kzz-1h-4DP" /]
  78.                     [/constraints]
  79.  [state key= "normal" title= "recover" ]
  80.                         [color key= "titleShadowColor" white= "0.5" alpha= "1" colorSpace= "calibratedWhite" /]
  81.  [/state]
  82.                     [connections]
  83.                         [action selector= "resume:" destination= "-1" eventType= "touchUpInside" id= "ms9-R9-B9B" /]
  84.                     [/connections]
  85.  [/button]
  86.                 [button opaque= "NO" contentMode= "scaleToFill" contentHorizontalAlignment= "center" contentVerticalAlignment= "center" buttonType= "roundedRect" lineBreakMode= "middleTruncation" translatesAutoresizingMaskIntoConstraints= "NO" id= "yMY-kU-iKL" ]
  87.                     [rect key= "frame" x= "225" y= "520" width= "70" height= "40" /]
  88.                     [constraints]
  89.                         [constraint firstAttribute= "height" constant= "40" id= "S7b-Pl-qKI" /]
  90.                         [constraint firstAttribute= "width" constant= "70" id= "gY7-vp-PUz" /]
  91.                     [/constraints]
  92.  [state key= "normal" title= "Cancel" ]
  93.                         [color key= "titleShadowColor" white= "0.5" alpha= "1" colorSpace= "calibratedWhite" /]
  94.  [/state]
  95.                     [connections]
  96.                         [action selector= "cancel:" destination= "-1" eventType= "touchUpInside" id= "ITC-zg-bfP" /]
  97.                     [/connections]
  98.  [/button]
  99.  [/subviews]
  100.             [color key= "backgroundColor" white= "1" alpha= "1" colorSpace= "custom" customColorSpace= "calibratedWhite" /]
  101.  [constraints]
  102.                 [constraint firstItem= "5kz-pB-9nK" firstAttribute= "centerY" secondItem= "YSM-n6-UM4" secondAttribute= "centerY" id= "4zt-gy-k65" /]
  103.                 [constraint firstItem= "qlQ-nM-BXU" firstAttribute= "leading" secondItem= "mwt-p9-tRE" secondAttribute= "leading" id= "RYu-qM-O8P" /]
  104.                 [constraint firstAttribute= "centerX" secondItem= "Me3-m2-iC4" secondAttribute= "centerX" id= "Ya8-bM-TaA" /]
  105.                 [constraint firstItem= "Me3-m2-iC4" firstAttribute= "top" secondItem= "i5M-Pr-FkT" secondAttribute= "top" constant= "160" id= "bOY-B5-is2" /]
  106.                 [constraint firstItem= "yMY-kU-iKL" firstAttribute= "centerY" secondItem= "5kz-pB-9nK" secondAttribute= "centerY" id= "dBh-1A-sIk" /]
  107.                 [constraint firstItem= "YSM-n6-UM4" firstAttribute= "leading" secondItem= "5kz-pB-9nK" secondAttribute= "trailing" constant= "10" id= "fYW-Jv-ro2" /]
  108.                 [constraint firstAttribute= "centerX" secondItem= "dlB-Qn-eOO" secondAttribute= "centerX" id= "gNK-NO-rth" /]
  109.                 [constraint firstItem= "dlB-Qn-eOO" firstAttribute= "top" secondItem= "i5M-Pr-FkT" secondAttribute= "top" constant= "104" id= "hwU-O2-Fed" /]
  110.                 [constraint firstItem= "mwt-p9-tRE" firstAttribute= "centerY" secondItem= "yMY-kU-iKL" secondAttribute= "centerY" id= "lGv-fH-Fh7" /]
  111.                 [constraint firstItem= "qlQ-nM-BXU" firstAttribute= "leading" secondItem= "Me3-m2-iC4" secondAttribute= "leading" id= "lus-oi-9SA" /]
  112.                 [constraint firstItem= "5kz-pB-9nK" firstAttribute= "leading" secondItem= "yMY-kU-iKL" secondAttribute= "trailing" constant= "10" id= "oge-T7-1td" /]
  113.                 [constraint firstItem= "qlQ-nM-BXU" firstAttribute= "top" secondItem= "i5M-Pr-FkT" secondAttribute= "top" constant= "180" id= "w3g-ej-P18" /]
  114.                 [constraint firstItem= "yMY-kU-iKL" firstAttribute= "leading" secondItem= "mwt-p9-tRE" secondAttribute= "trailing" constant= "10" id= "xCX-1F-xOv" /]
  115.                 [constraint firstAttribute= "bottom" secondItem= "mwt-p9-tRE" secondAttribute= "bottom" constant= "40" id= "yBq-He-Jv8" /]
  116.  [/constraints]
  117.  [/view]
  118.  [/objects]
  119.  [/document]

#p#

AFNetworkingViewController.h

  1.  # import # import   "MBProgressHUD.h"   
  2.   
  3.  @interface AFNetworkingViewController : UIViewController
  4.  @property (strong, nonatomic) MBProgressHUD *hud; 
  5.   
  6.  @property (strong, nonatomic) IBOutlet UILabel *lblFileName;
  7.  @property (strong, nonatomic) IBOutlet UILabel *lblMessage;
  8.  @property (strong, nonatomic) IBOutlet UIButton *btnDownloadFileByConnection;
  9.  @property (strong, nonatomic) IBOutlet UIButton *btnDownloadFileBySession; 
  10.   
  11.  @end  

AFNetworkingViewController.m

  1.  # import   "AFNetworkingViewController.h"  
  2.  # import   "AFNetworking.h"  
  3.  # import   "AFNetworkActivityIndicatorManager.h"  
  4.  # import   "UIButton+BeautifulButton.h"   
  5.   
  6.  @interface AFNetworkingViewController ()
  7.  - ( void )showAlert:(NSString *)msg;
  8.  - ( void )checkNetwork;
  9.  - ( void )layoutUI;
  10.  - (NSMutableURLRequest *)downloadRequest;
  11.  - (NSURL *)saveURL:(NSURLResponse *)response deleteExistFile:(BOOL)deleteExistFile;
  12.  - ( void )updateProgress:(int64_t)receiveDataLength totalDataLength:(int64_t)totalDataLength;
  13.  @end   
  14.   
  15.  @implementation AFNetworkingViewController 
  16.   
  17.  - ( void )viewDidLoad {
  18.  [ super viewDidLoad]; 
  19.       
  20.  [self layoutUI];
  21.  } 
  22.   
  23.  - ( void )didReceiveMemoryWarning {
  24.     [ super didReceiveMemoryWarning];
  25.  // Dispose of any resources that can be recreated.  
  26.  } 
  27.   
  28.  - ( void )showAlert:(NSString *)msg {
  29.  UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@ "Network Situation"  
  30.                                                     message:msg
  31.                                                    delegate:self
  32.                                           cancelButtonTitle:nil
  33.  otherButtonTitles:@ "OK" , nil];
  34.  [alert show];
  35.  } 
  36.   
  37.  - ( void )checkNetwork {
  38.     NSURL *baseURL = [NSURL URLWithString:@ "http://www.baidu.com/" ];
  39.     AFHTTPRequestOperationManager *manager = [[AFHTTPRequestOperationManager alloc] initWithBaseURL:baseURL]; 
  40.       
  41.     NSOperationQueue *operationQueue = manager.operationQueue;
  42.     [manager.reachabilityManager setReachabilityStatusChangeBlock:^(AFNetworkReachabilityStatus status) {
  43.  switch (status) {
  44.  case AFNetworkReachabilityStatusReachableViaWiFi:
  45.  [self showAlert:@ "Under Wi-Fi Network" ];
  46.                 [operationQueue setSuspended:NO];
  47.  break ;
  48.  case AFNetworkReachabilityStatusReachableViaWWAN:
  49.  [self showAlert:@ "Under 2G/3G/4G cellular mobile network" ];
  50.                 [operationQueue setSuspended:YES];
  51.  break ;
  52.  case AFNetworkReachabilityStatusNotReachable:
  53.  default :
  54.  [self showAlert:@ "Net not connected" ];
  55.                 [operationQueue setSuspended:YES];
  56.  break ;
  57.  }
  58.  }]; 
  59.       
  60.     [manager.reachabilityManager startMonitoring];
  61.  } 
  62.   
  63.  - ( void )layoutUI {
  64.     self.navigationItem.title = kTitleOfAFNetworking;
  65.     self.view.backgroundColor = [UIColor colorWithWhite: 0.95 alpha: 1.000 ]; 
  66.       
  67.  //In the conditional expression, "?:" can mean that the latter assignment is used only when the condition is not true, otherwise the former assignment is used for conditional judgment.  
  68.  //The following statement is equivalent to: UIButton *btn = _btnDownloadFileByConnection ? _btnDownloadFileByConnection : [UIButton new];  
  69.  //In .NET, it is equivalent to using "??"; in JavaScript, it is equivalent to using "||" to achieve this similar judgment  
  70.     UIButton *btn = _btnDownloadFileByConnection ?: [UIButton new ];
  71.     [btn beautifulButton:nil];
  72.     [_btnDownloadFileBySession beautifulButton:[UIColor orangeColor]]; 
  73.       
  74.  //Progress effect  
  75.     _hud = [[MBProgressHUD alloc] initWithView:self.view];
  76.     _hud.mode = MBProgressHUDModeDeterminate;
  77.  _hud.labelText = @ "Download..." ;
  78.  [_hud hide:YES];
  79.     [self.view addSubview:_hud]; 
  80.       
  81.  //Check the network status  
  82.  [self checkNetwork]; 
  83.       
  84.  //Activate the network activity indicator; it will display or hide the network activity indicator in real time according to the network interaction situation; it realizes the control of [UIApplication sharedApplication].networkActivityIndicatorVisible through the "notification and message mechanism"  
  85.     [AFNetworkActivityIndicatorManager sharedManager].enabled = YES;
  86.  } 
  87.   
  88.  - (NSMutableURLRequest *)downloadRequest {
  89.     NSString *fileURLStr = kFileURLStr;
  90.  //Encoding operation; the corresponding decoding operation is to use the stringByRemovingPercentEncoding method  
  91.     fileURLStr = [fileURLStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
  92.     NSURL *fileURL = [NSURL URLWithString:fileURLStr]; 
  93.       
  94.  //Create a request  
  95.     NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:fileURL];
  96.  return request;
  97.  } 
  98.   
  99.  - (NSURL *)saveURL:(NSURLResponse *)response deleteExistFile:(BOOL)deleteExistFile {
  100.     NSString *fileName = response ? [response suggestedFilename] : _lblFileName.text; 
  101.       
  102.  //Method 1  
  103.  //    NSString *savePath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject];  
  104.  //    savePath = [savePath stringByAppendingPathComponent:fileName];  
  105.  //    NSURL *saveURL = [NSURL fileURLWithPath:savePath];   
  106.       
  107.  //Method 2  
  108.     NSURL *saveURL = [[NSFileManager defaultManager] URLForDirectory:NSCachesDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:NO error:nil];
  109.     saveURL = [saveURL URLByAppendingPathComponent:fileName];
  110.     NSString *savePath = [saveURL path]; 
  111.       
  112.  if (deleteExistFile) {
  113.  NSError *saveError;
  114.         NSFileManager *fileManager = [NSFileManager defaultManager];
  115.  //Judge whether the old target file exists, and remove it first if it exists; avoid the problem of being unable to copy  
  116.  if ([fileManager fileExistsAtPath:savePath]) {
  117.             [fileManager removeItemAtPath:savePath error:&saveError];
  118.  if (saveError) {
  119.  NSLog(@ "Failed to remove the old target file, error message: %@" , saveError.localizedDescription);
  120.  }
  121.  }
  122.  } 
  123.       
  124.  return saveURL;
  125.  } 
  126.   
  127.  - ( void )updateProgress:(int64_t)receiveDataLength totalDataLength:(int64_t)totalDataLength; {
  128.  dispatch_async(dispatch_get_main_queue(), ^{ //Use the main queue asynchronous method (main thread) to perform update UI operations  
  129.         _hud.progress = ( float )receiveDataLength / totalDataLength; 
  130.           
  131.  if (receiveDataLength == totalDataLength) {
  132.  _lblMessage.text = receiveDataLength < 0 ? @ "Download failed" : @ "Download completed" ;
  133.  //kApplication.networkActivityIndicatorVisible = NO;  
  134.  [_hud hide:YES];
  135.  } else {
  136.  _lblMessage.text = @ "Download..." ;
  137.  //kApplication.networkActivityIndicatorVisible = YES;  
  138.  [_hud show:YES];
  139.  }
  140.  });
  141.  } 
  142.   
  143.  - (IBAction)downloadFileByConnection:(id)sender {
  144.  //Create a request  
  145.     NSMutableURLRequest *request = [self downloadRequest]; 
  146.       
  147.  //Create a request operation  
  148.     AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
  149.     NSString *savePath = [[self saveURL:nil deleteExistFile:NO] path]; 
  150.       
  151.     [operation setDownloadProgressBlock:^(NSUInteger bytesRead, long   long totalBytesRead, long   long totalBytesExpectedToRead) {
  152.  NSLog(@ "Response data has been received, the data length is %lld bytes..." , totalBytesRead); 
  153.           
  154.         [self updateProgress:totalBytesRead totalDataLength:totalBytesExpectedToRead];
  155.  }]; 
  156.       
  157.     [operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
  158.  NSLog(@ "All response data has been received" ); 
  159.           
  160.         NSData *data = (NSData *)responseObject;
  161.  [data writeToFile:savePath atomically:YES]; //The object type of responseObject is NSData   
  162.           
  163.         [self updateProgress: 100 totalDataLength: 100 ];
  164.     } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
  165.  NSLog(@ "Download failed, error message: %@" , error.localizedDescription); 
  166.           
  167.         [self updateProgress:- 1 totalDataLength:- 1 ];
  168.  }]; 
  169.       
  170.  //Start the request operation  
  171.  [operation start];
  172.  } 
  173.   
  174.  - (IBAction)downloadFileBySession:(id)sender {
  175.  //Create a request  
  176.     NSMutableURLRequest *request = [self downloadRequest]; 
  177.       
  178.  //Create session configuration "In-process session"  
  179.     NSURLSessionConfiguration *sessionConfiguration = [NSURLSessionConfiguration defaultSessionConfiguration];
  180.  sessionConfiguration.timeoutIntervalForRequest = 60.0 ; //Request timeout time; default is 60 seconds  
  181.  sessionConfiguration.allowsCellularAccess = YES; // Whether to allow cellular network access (2G/3G/4G)  
  182.  sessionConfiguration.HTTPMaximumConnectionsPerHost = 4 ; //Limit the maximum number of connections per time; the default value in iOS is 4   
  183.       
  184.  //Create a session manager  
  185.     AFURLSessionManager *sessionManager = [[AFURLSessionManager alloc] initWithSessionConfiguration:sessionConfiguration]; 
  186.       
  187.  //Create a session download task and start it; execute in a non-main thread  
  188.     NSURLSessionDownloadTask *task = [sessionManager
  189.                                       downloadTaskWithRequest:request
  190.                                       progress:nil
  191.                                       destination:^ NSURL*(NSURL *targetPath, NSURLResponse *response) {
  192.  //When the sessionManager calls the setDownloadTaskDidFinishDownloadingBlock: method, and the return value of the method code block is not nil (high priority), the following two sentences of code are not executed (low priority)  
  193.  NSLog(@ "temporary save path after download: %@" , targetPath);
  194.  return [self saveURL:response deleteExistFile:YES];
  195.                                       } completionHandler:^ (NSURLResponse *response, NSURL *filePath, NSError *error) {
  196.  if (!error) {
  197.  NSLog(@ "Save path after download: %@" , filePath); //The path returned for the above code block   
  198.                                                 
  199.                                               [self updateProgress: 100 totalDataLength: 100 ];
  200.                                           } else {
  201.  NSLog(@ "Download failed, error message: %@" , error.localizedDescription); 
  202.                                                 
  203.                                               [self updateProgress:- 1 totalDataLength:- 1 ];
  204.                                           } 
  205.                                             
  206.                                           [_hud hide:YES];
  207.                                       }]; 
  208.       
  209.  //Method operations similar to NSURLSessionDownloadDelegate  
  210.  //- (void)URLSession:(NSURLSession *)session downloadTask:(NSURLSessionDownloadTask *)downloadTask didWriteData:(int64_t)bytesWritten totalBytesWritten:(int64_t)totalBytesWritten totalBytesExpectedToWrite:(int64_t)totalBytesExpectedToWrite;  
  211.     [sessionManager setDownloadTaskDidWriteDataBlock:^ (NSURLSession *session, NSURLSessionDownloadTask *downloadTask, int64_t bytesWritten, int64_t totalBytesWritten, int64_t totalBytesExpectedToWrite) {
  212.  NSLog(@ "Response data has been received, the data length is %lld bytes..." , totalBytesWritten); 
  213.           
  214.         [self updateProgress:totalBytesWritten totalDataLength:totalBytesExpectedToWrite];
  215.  }]; 
  216.       
  217.  //- (void)URLSession:(NSURLSession *)session downloadTask:(NSURLSessionDownloadTask *)downloadTask didFinishDownloadingToURL:(NSURL *)location;  
  218.     [sessionManager setDownloadTaskDidFinishDownloadingBlock:^ NSURL*(NSURLSession *session, NSURLSessionDownloadTask *downloadTask, NSURL *location) {
  219.  NSLog(@ "All response data has been received, temporary save path after download: %@" , location);
  220.  return [self saveURL:nil deleteExistFile:YES];
  221.  }]; 
  222.       
  223.  [task resume];
  224.  } 
  225.   
  226.  @end  

AFNetworkingViewController.xib

  1.  [?xml version= "1.0" encoding= "UTF-8" standalone= "no" ?]
  2.  [document type= "com.apple.InterfaceBuilder3.CocoaTouch.XIB" version= "3.0" toolsVersion= "7706" systemVersion= "14E46" targetRuntime= "iOS.CocoaTouch" propertyAccessControl= "none" useAutolayout= "YES" useTraitCollections= "YES" ]
  3.  [dependencies]
  4.         [deployment identifier= "iOS" /]
  5.         [plugIn identifier= "com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version= "7703" /]
  6.  [/dependencies]
  7.  [objects]
  8.         [placeholder placeholderIdentifier= "IBFilesOwner" id= "-1" userLabel= "File's Owner" customClass= "AFNetworkingViewController" ]
  9.  [connections]
  10.                 [outlet property= "btnDownloadFileByConnection" destination= "IkH-un-SOz" id= "gDd-6X-uxU" /]
  11.                 [outlet property= "btnDownloadFileBySession" destination= "mwt-p9-tRE" id= "5Qk-Zm-V3w" /]
  12.                 [outlet property= "lblFileName" destination= "dlB-Qn-eOO" id= "NdS-9n-7KX" /]
  13.                 [outlet property= "lblMessage" destination= "qlQ-nM-BXU" id= "tRe-SR-AQE" /]
  14.                 [outlet property= "view" destination= "i5M-Pr-FkT" id= "sfx-zR-JGt" /]
  15.  [/connections]
  16.  [/placeholder]
  17.         [placeholder placeholderIdentifier= "IBFirstResponder" id= "-2" customClass= "UIResponder" /]
  18.         [view clearsContextBeforeDrawing= "NO" contentMode= "scaleToFill" id= "i5M-Pr-FkT" ]
  19.             [rect key= "frame" x= "0.0" y= "0.0" width= "600" height= "600" /]
  20.             [autoresizingMask key= "autoresizingMask" widthSizable= "YES" heightSizable= "YES" /]
  21.  [subviews]
  22.                 [label opaque= "NO" userInteractionEnabled= "NO" contentMode= "left" horizontalHuggingPriority= "251" verticalHuggingPriority= "251" text= "metro_demo使用Highcharts实现图表展示.zip" lineBreakMode= "tailTruncation" baselineAdjustment= "alignBaselines" adjustsFontSizeToFit= "NO" translatesAutoresizingMaskIntoConstraints= "NO" id= "dlB-Qn-eOO" ]
  23.                     [rect key= "frame" x= "145" y= "104" width= "309.5" height= "18" /]
  24.                     [fontDescription key= "fontDescription" type= "boldSystem" pointSize= "15" /]
  25.                     [color key= "textColor" cocoaTouchSystemColor= "darkTextColor" /]
  26.                     [nil key= "highlightedColor" /]
  27.  [/label]
  28.                 [button opaque= "NO" contentMode= "scaleToFill" contentHorizontalAlignment= "center" contentVerticalAlignment= "center" buttonType= "roundedRect" lineBreakMode= "middleTruncation" translatesAutoresizingMaskIntoConstraints= "NO" id= "mwt-p9-tRE" ]
  29.                     [rect key= "frame" x= "175" y= "520" width= "250" height= "40" /]
  30.                     [constraints]
  31.                         [constraint firstAttribute= "width" constant= "250" id= "I5D-tA-ffH" /]
  32.                         [constraint firstAttribute= "height" constant= "40" id= "Y8C-D4-IVr" /]
  33.                     [/constraints]
  34.  [state key= "normal" title= "Download based on NSURLSession" ]
  35.                         [color key= "titleShadowColor" white= "0.5" alpha= "1" colorSpace= "calibratedWhite" /]
  36.  [/state]
  37.                     [connections]
  38.                         [action selector= "downloadFileBySession:" destination= "-1" eventType= "touchUpInside" id= "z6s-cq-dag" /]
  39.                     [/connections]
  40.  [/button]
  41.                 [label opaque= "NO" userInteractionEnabled= "NO" contentMode= "left" horizontalHuggingPriority= "251" verticalHuggingPriority= "251" text= "Label" lineBreakMode= "tailTruncation" baselineAdjustment= "alignBaselines" adjustsFontSizeToFit= "NO" translatesAutoresizingMaskIntoConstraints= "NO" id= "qlQ-nM-BXU" ]
  42.                     [rect key= "frame" x= "145" y= "140" width= "37.5" height= "18" /]
  43.                     [fontDescription key= "fontDescription" type= "system" pointSize= "15" /]
  44.                     [color key= "textColor" red= "0.0" green= "0.50196081399917603" blue= "1" alpha= "1" colorSpace= "calibratedRGB" /]
  45.                     [nil key= "highlightedColor" /]
  46.                     [userDefinedRuntimeAttributes]
  47.                         [userDefinedRuntimeAttribute type= "string" keyPath= "text" value= "" /]
  48.                     [/userDefinedRuntimeAttributes]
  49.  [/label]
  50.                 [button opaque= "NO" contentMode= "scaleToFill" contentHorizontalAlignment= "center" contentVerticalAlignment= "center" buttonType= "roundedRect" lineBreakMode= "middleTruncation" translatesAutoresizingMaskIntoConstraints= "NO" id= "IkH-un-SOz" ]
  51.                     [rect key= "frame" x= "174" y= "460" width= "250" height= "40" /]
  52.                     [constraints]
  53.                         [constraint firstAttribute= "width" constant= "250" id= "3a7-Og-iWa" /]
  54.                         [constraint firstAttribute= "height" constant= "40" id= "mc0-yK-hWE" /]
  55.                     [/constraints]
  56.  [state key= "normal" title= "Download based on NSURLConnection" ]
  57.                         [color key= "titleShadowColor" white= "0.5" alpha= "1" colorSpace= "calibratedWhite" /]
  58.  [/state]
  59.                     [connections]
  60.                         [action selector= "downloadFileByConnection:" destination= "-1" eventType= "touchUpInside" id= "1ko-jP-kCo" /]
  61.                     [/connections]
  62.  [/button]
  63.  [/subviews]
  64.             [color key= "backgroundColor" white= "1" alpha= "1" colorSpace= "custom" customColorSpace= "calibratedWhite" /]
  65.  [constraints]
  66.                 [constraint firstItem= "mwt-p9-tRE" firstAttribute= "top" secondItem= "IkH-un-SOz" secondAttribute= "bottom" constant= "20" id= "Sye-JW-gux" /]
  67.                 [constraint firstAttribute= "centerX" secondItem= "dlB-Qn-eOO" secondAttribute= "centerX" id= "gNK-NO-rth" /]
  68.                 [constraint firstItem= "dlB-Qn-eOO" firstAttribute= "top" secondItem= "i5M-Pr-FkT" secondAttribute= "top" constant= "104" id= "hwU-O2-Fed" /]
  69.                 [constraint firstAttribute= "centerX" secondItem= "IkH-un-SOz" secondAttribute= "centerX" constant= "1" id= "lF1-Yf-Axs" /]
  70.                 [constraint firstAttribute= "centerX" secondItem= "mwt-p9-tRE" secondAttribute= "centerX" id= "teN-3t-8Gc" /]
  71.                 [constraint firstItem= "qlQ-nM-BXU" firstAttribute= "top" secondItem= "i5M-Pr-FkT" secondAttribute= "top" constant= "140" id= "w3g-ej-P18" /]
  72.                 [constraint firstItem= "dlB-Qn-eOO" firstAttribute= "leading" secondItem= "qlQ-nM-BXU" secondAttribute= "leading" constant= "0.5" id= "wMU-pU-z9f" /]
  73.                 [constraint firstAttribute= "bottom" secondItem= "mwt-p9-tRE" secondAttribute= "bottom" constant= "40" id= "yBq-He-Jv8" /]
  74.  [/constraints]
  75.  [/view]
  76.  [/objects]
  77.  [/document] 
  78.   
  79.  View Cod

AppDelegate.h

  1.  # import   @interface AppDelegate : UIResponder @property (strong, nonatomic) UIWindow *window;
  2.  @property (strong, nonatomic) UINavigationController *navigationController; 
  3.   
  4.  @end  

AppDelegate.m

  1.  # import   "AppDelegate.h"  
  2.  # import   "ViewController.h"   
  3.   
  4.  @interface AppDelegate () 
  5.   
  6.  @end   
  7.   
  8.  @implementation AppDelegate 
  9.   
  10.   
  11.  - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
  12.     _window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
  13.     ViewController *viewController = [[ViewController alloc]
  14.                                       initWithSampleNameArray:@[ kTitleOfNSURLConnection,
  15.                                                                  kTitleOfNSURLConnectionDelegate,
  16.                                                                  kTitleOfNSURLSession,
  17.                                                                  kTitleOfNSURLSessionDelegate,
  18.                                                                  kTitleOfAFNetworking]];
  19.     _navigationController = [[UINavigationController alloc] initWithRootViewController:viewController];
  20.     _window.rootViewController = _navigationController;
  21.  //[_window addSubview:_navigationController.view]; //When _window.rootViewController is associated, this sentence is optional  
  22.     [_window makeKeyAndVisible];
  23.  return YES;
  24.  } 
  25.   
  26.  - ( void )applicationWillResignActive:(UIApplication *)application {
  27.  } 
  28.   
  29.  - ( void )applicationDidEnterBackground:(UIApplication *)application {
  30.  } 
  31.   
  32.  - ( void )applicationWillEnterForeground:(UIApplication *)application {
  33.  } 
  34.   
  35.  - ( void )applicationDidBecomeActive:(UIApplication *)application {
  36.  } 
  37.   
  38.  - ( void )applicationWillTerminate:(UIApplication *)application {
  39.  } 
  40.   
  41.  @end  

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