• get請求
  -1

 // 獲得NSURLSession對象
    NSURLSession *session = [NSURLSession sharedSession];
    
    // 創(chuàng)建任務
    NSURLSessionDataTask *task = [session dataTaskWithRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"http://120.25.226.186:32812/login?username=123&pwd=4324"]] completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
        NSLog(@"%@", [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:nil]);
    }];
    // 啟動任務
    [task resume];

-2

// 獲得NSURLSession對象
    NSURLSession *session = [NSURLSession sharedSession];
    
    // 創(chuàng)建任務
    NSURLSessionDataTask *task = [session dataTaskWithURL:[NSURL URLWithString:@"http://120.25.226.186:32812/login?username=123&pwd=4324"] completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
        NSLog(@"%@", [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:nil]);
    }];
    
    // 啟動任務
    [task resume];

• post請求
  -1

 // 獲得NSURLSession對象
    NSURLSession *session = [NSURLSession sharedSession];
    
    // 創(chuàng)建請求
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:@"http://120.25.226.186:32812/login"]];
    request.HTTPMethod = @"POST"; // 請求方法
    request.HTTPBody = [@"username=520it&pwd=520it" dataUsingEncoding:NSUTF8StringEncoding]; // 請求體
    
    // 創(chuàng)建任務
    NSURLSessionDataTask *task = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
        NSLog(@"%@", [NSJSONSerialization JSONObjectWithData:data options:kNilOptions error:nil]);
    }];
    
    // 啟動任務
    [task resume];

-2 文件下載

 // 獲得NSURLSession對象
    NSURLSession *session = [NSURLSession sharedSession];
    
    // 獲得下載任務
    NSURLSessionDownloadTask *task = [session downloadTaskWithURL:[NSURL URLWithString:@"http://120.25.226.186:32812/resources/videos/minion_01.mp4"] completionHandler:^(NSURL *location, NSURLResponse *response, NSError *error) {
        // 文件將來存放的真實路徑
        NSString *file = [[NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject] stringByAppendingPathComponent:response.suggestedFilename];
        
        // 剪切l(wèi)ocation的臨時文件到真實路徑
        NSFileManager *mgr = [NSFileManager defaultManager];
        [mgr moveItemAtURL:location toURL:[NSURL fileURLWithPath:file] error:nil];
    }];
    
    // 啟動任務
    [task resume];

--3 文件下載(通過代理方法監(jiān)聽下載過程)

// 獲得NSURLSession對象
    NSURLSession *session = [NSURLSession sessionWithConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration] delegate:self delegateQueue:[[NSOperationQueue alloc] init]];
    
    // 獲得下載任務
    NSURLSessionDownloadTask *task = [session downloadTaskWithURL:[NSURL URLWithString:@"http://120.25.226.186:32812/resources/videos/minion_01.mp4"]];
    
    // 啟動任務
    [task resume];

//切記代理對象遵守<NSURLSessionDownloadDelegate>協(xié)議
/**
 * 1.接收到服務器的響應
 */

- (void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveResponse:(NSURLResponse *)response completionHandler:(void (^)(NSURLSessionResponseDisposition))completionHandler
{
    NSLog(@"%s", __func__);
    
    // 允許處理服務器的響應，才會繼續(xù)接收服務器返回的數據
    completionHandler(NSURLSessionResponseAllow);
    
    // void (^)(NSURLSessionResponseDisposition)
}

/**
 * 2.接收到服務器的數據（可能會被調用多次）
 */
- (void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveData:(NSData *)data
{
    NSLog(@"%s", __func__);
}

/**
 * 3.請求成功或者失?。ㄈ绻。琫rror有值）
 */
- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error
{
    NSLog(@"%s", __func__);
}