AFHTTPSessionManager *manager = [AFHTTPSessionManager manager];

    manager.responseSerializer = [AFJSONResponseSerializer serializer];

    manager.requestSerializer=[AFJSONRequestSerializer serializer];

    [manager POST:urlStr parameters:parma progress:^(NSProgress * _Nonnull uploadProgress) {

    } success:^(NSURLSessionDataTask * _Nonnull task, id  _Nullable responseObject) {

        block(responseObject,nil);

    } failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {

        [self showAlertView:[error description]];

        [self hideHud];

        block(nil,error);

    }];