前提，部分参考资料已忘记，本文只提供自己备用，部分参考望见谅。

1.请求设置：需要设置代理p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #703daa}span.s1 {font-variant-ligatures: no-common-ligatures}

NSURLSessionDataDelegate

p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #008400}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #3d1d81}p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #703daa}span.s1 {font-variant-ligatures: no-common-ligatures}span.s2 {font: 11.0px 'Heiti SC Light'; font-variant-ligatures: no-common-ligatures}span.s3 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s4 {font-variant-ligatures: no-common-ligatures; color: #3d1d81}span.s5 {font-variant-ligatures: no-common-ligatures; color: #000000}span.s6 {font-variant-ligatures: no-common-ligatures; color: #272ad8}span.s7 {font-variant-ligatures: no-common-ligatures; color: #d12f1b}span.s8 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}

//创建url对象
NSURL *url = [NSURL URLWithString:urlString];
//创建请求
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url cachePolicy:NSURLRequestReloadIgnoringLocalCacheData timeoutInterval:20];
[request setHTTPMethod:@"POST"];

NSData *data = [paramString dataUsingEncoding:NSUTF8StringEncoding];
[request setHTTPBody:data];


NSURLSessionConfiguration *sessionConfiguration = [NSURLSessionConfiguration defaultSessionConfiguration];
NSURLSession *session = [NSURLSession sessionWithConfiguration:sessionConfiguration delegate:self delegateQueue:[NSOperationQueue mainQueue]];
NSURLSessionDataTask *task = [session dataTaskWithRequest:request];
[task resume];

2.实现代理
p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo}p.p2 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #008400}p.p3 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #3d1d81}p.p4 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px 'Heiti SC Light'; color: #008400}p.p5 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #703daa}p.p6 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #d12f1b}p.p7 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; color: #4f8187}p.p8 {margin: 0.0px 0.0px 0.0px 0.0px; font: 11.0px Menlo; min-height: 13.0px}span.s1 {font-variant-ligatures: no-common-ligatures}span.s2 {font-variant-ligatures: no-common-ligatures; color: #bb2ca2}span.s3 {font-variant-ligatures: no-common-ligatures; color: #703daa}span.s4 {font-variant-ligatures: no-common-ligatures; color: #000000}span.s5 {font: 11.0px 'Heiti SC Light'; font-variant-ligatures: no-common-ligatures}span.s6 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures; color: #000000}span.s7 {font: 11.0px Menlo; font-variant-ligatures: no-common-ligatures}span.s8 {font-variant-ligatures: no-common-ligatures; color: #3d1d81}span.s9 {font-variant-ligatures: no-common-ligatures; color: #78492a}span.s10 {font-variant-ligatures: no-common-ligatures; color: #4f8187}

• (void)URLSession:(NSURLSession *)session
  didReceiveChallenge:(NSURLAuthenticationChallenge *)challenge
  completionHandler:(void (^)(NSURLSessionAuthChallengeDisposition disposition, NSURLCredential *credential))completionHandler
  {
  //AFNetworking中的处理方式
  NSURLSessionAuthChallengeDisposition disposition = NSURLSessionAuthChallengePerformDefaultHandling;
  __block NSURLCredential credential = nil;
  //判断服务器返回的证书是否是服务器信任的
  if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust]) {
  credential = [NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust];
  /disposition：如何处理证书
  NSURLSessionAuthChallengePerformDefaultHandling:默认方式处理
  NSURLSessionAuthChallengeUseCredential：使用指定的证书 NSURLSessionAuthChallengeCancelAuthenticationChallenge：取消请求
  */
  if (credential) {
  disposition = NSURLSessionAuthChallengeUseCredential;
  } else {
  disposition = NSURLSessionAuthChallengePerformDefaultHandling;
  }
  } else {
  disposition = NSURLSessionAuthChallengeCancelAuthenticationChallenge;
  }
  //安装证书
  if (completionHandler) {
  completionHandler(disposition, credential);
  }
  }
  // 接收到服务器的响应
• (void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveResponse:(NSURLResponse *)response completionHandler:(void (^)(NSURLSessionResponseDisposition))completionHandler
  {
  NSLog(@"didReceiveResponse");
  completionHandler(NSURLSessionResponseAllow);
  }
  // 接收到服务器返回的数据
• (void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveData:(NSData *)data
  {
  NSDictionary *dic = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:nil];
  NSString *dataString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
  NSLog(@"didReceiveData %@ %@",dic,dataString);
  }
  // 请求完毕
• (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error
  {
  NSLog(@"didCompleteWithError %@",error);
  }