iOS 11.1.1 af网络请求失败的解决办法

升级iOS 11.1.1之后出现网络请求错误

Error Domain=NSURLErrorDomain Code=-1004 "未能连接到服务器。" UserInfo={NSUnderlyingError=0x1c4a53dd0 {Error Domain=kCFErrorDomainCFNetwork Code=-1004 "(null)" UserInfo={_kCFStreamErrorCodeKey=61, _kCFStreamErrorDomainKey=1}}, NSErrorFailingURLStringKey=http://www.cheshizh.com/?m=app&c=app_mall&a=app_focus&city=%E9%95%BF%E6%98%A51, NSErrorFailingURLKey=http://www.cheshizh.com/?m=app&c=app_mall&a=app_focus&city=%E9%95%BF%E6%98%A51, _kCFStreamErrorDomainKey=1, _kCFStreamErrorCodeKey=61, NSLocalizedDescription=未能连接到服务器。}

iOS 11的ATS相关问题。

iOS 11情况下AFNetworking 3.0如果不配置AFSecurityPolicy是工作不了的。

（1）从服务器端下载.crt文件，比如文件名叫 serverSecurity.crt

  (2)   将文件转成.cer文件.终端命令:openssl x509 -in serverSecurity.crt -out https.cer -outform der 注意：https是一个文件名，可以换成别的名字

    （3）导入.cer文件到项目 。导入的时候注意选中target

     (4) 配置ACNetWorkManager的securityPolicy属性，贴代码：

NSString *cerPath = [[NSBundlemainBundle] pathForResource:@"https"ofType:@"cer"];

        NSData *certData  = [NSDatadataWithContentsOfFile:cerPath];

        AFSecurityPolicy *securityPolicy = [AFSecurityPolicypolicyWithPinningMode:AFSSLPinningModeCertificate];

        securityPolicy.allowInvalidCertificates =YES;

        securityPolicy.pinnedCertificates = [NSSetsetWithObject:certData];

        securityPolicy.validatesDomainName =YES;

        manager.securityPolicy = securityPolicy;

      总结：（1）配置过程不难

   （2）Apple不再向开发者妥协

    (3)iOS应用越来越安全

  AFHTTPSessionManager * session = [AFHTTPSessionManager manager]; 
    
    NSString * cerPath = [[NSBundle mainBundle] pathForResource：@“mnchip”ofType：@“cer”]; 
    NSData * cerDat = [NSData dataWithContentsOfFile：cerPath]; 
    AFSecurityPolicy * SECURITYPOLICY = [AFSecurityPolicy policyWithPinningMode：AFSSLPinningModeCertificate withPinnedCertificates：[NSSet中setWithObject：cerDat]]; 
    //允许自检证书
    securityPolicy.allowInvalidCertificates = YES; 
    //域名与服务器一致
    securityPolicy.validatesDomainName = YES; 
    session.securityPolicy = [OperationHelper customSecurityPolicy]; 
    的NSDictionary * PARAMS = [NSDictionary的dictionaryWithObjectsAndKeys：@ “DoPassword”，VALUE_NAME，temDevicenum，VALUE_ID，@（时间），VALUE_TIMESTAMP，MMM，VALUE_MD5，@ “” @ “cPassword”，零]。
    
    [session POST：KURL参数：params进度：nil成功：^（NSURLSessionDataTask * _Nonnull任务，id _Nullable响应对象）{ 
        NSDictionary * dictionary =（NSDictionary *）responseObject; 
        if（[dictionary [@“ReturnValue”] intValue] == 1）{ 
            // NSLog（@“请求登陆口令成功”）; 
        } 
    }失败：^（NSURLSessionDataTask * _Nullable任务，NSError * _Nonnull错误）{ 
        // NSLog（@