<key>NSAppTransportSecurity</key>
  <dict>
    <key>NSAllowsArbitraryLoads</key>
    <true/>
  </dict>

- (void)connection:(NSURLConnection *)connection willSendRequestForAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge{

  if(challenge.protectionSpace.authenticationMethod == NSURLAuthenticationMethodServerTrust) {
    // 告诉服务器，客户端信任证书
    // 创建凭据对象
    NSURLCredential *credntial = [NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust];
    // 告诉服务器信任证书
    [challenge.sender useCredential:credntial forAuthenticationChallenge:challenge];
  }
}

- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didReceiveChallenge:(NSURLAuthenticationChallenge *)challenge completionHandler:(void (^)(NSURLSessionAuthChallengeDisposition disposition, NSURLCredential * __nullable credential))completionHandler {

  // 判断是否是信任服务器证书
  if(challenge.protectionSpace.authenticationMethod == NSURLAuthenticationMethodServerTrust) {
    // 告诉服务器，客户端信任证书
    // 创建凭据对象
    NSURLCredential *credntial = [NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust];
    // 通过completionHandler告诉服务器信任证书
    completionHandler(NSURLSessionAuthChallengeUseCredential,credntial);
  }
  NSLog(@"protectionSpace = %@",challenge.protectionSpace);
}

// 1.初始化单例类
  AFHTTPRequestOperationManager *mgr = [AFHTTPRequestOperationManager manager];
  mgr.securityPolicy.SSLPinningMode = AFSSLPinningModeCertificate;
  // 2.设置证书模式
  NSString * cerPath = [[NSBundle mainBundle] pathForResource:@"xxx" ofType:@"cer"];
  NSData * cerData = [NSData dataWithContentsOfFile:cerPath];
  mgr.securityPolicy.pinnedCertificates = [[NSArray alloc] initWithObjects:cerData, nil];
  // 客户端是否信任非法证书
  mgr.securityPolicy.allowInvalidCertificates = YES;
  // 是否在证书域字段中验证域名
  [mgr.securityPolicy setValidatesDomainName:NO];

 // 1.初始化单例类
  AFHTTPRequestOperationManager *mgr = [AFHTTPRequestOperationManager manager];
  mgr.securityPolicy.SSLPinningMode = AFSSLPinningModeCertificate;
  // 2.设置非校验证书模式
  mgr.securityPolicy = [AFSecurityPolicy policyWithPinningMode:AFSSLPinningModeNone];
  mgr.securityPolicy.allowInvalidCertificates = YES;
  [mgr.securityPolicy setValidatesDomainName:NO];

// 1.初始化
   AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];
  manager.securityPolicy.SSLPinningMode = AFSSLPinningModeCertificate;
  // 2.设置证书模式
  NSString * cerPath = [[NSBundle mainBundle] pathForResource:@"xxx" ofType:@"cer"];
  NSData * cerData = [NSData dataWithContentsOfFile:cerPath];
  manager.securityPolicy = [AFSecurityPolicy policyWithPinningMode:AFSSLPinningModeCertificate withPinnedCertificates:[[NSSet alloc] initWithObjects:cerData, nil]];
  // 客户端是否信任非法证书
  mgr.securityPolicy.allowInvalidCertificates = YES;
  // 是否在证书域字段中验证域名
  [mgr.securityPolicy setValidatesDomainName:NO];

// 1.初始化
   AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];
  // 2.设置非校验证书模式
  manager.securityPolicy = [AFSecurityPolicy policyWithPinningMode:AFSSLPinningModeNone];
  manager.securityPolicy.allowInvalidCertificates = YES;
  [manager.securityPolicy setValidatesDomainName:NO];