[置顶] iOS开发AFN3.0中json解析返回3840获取error自己解析

因为后台原因，如果请求失败，返回的error错误信息是AFN中默认json解析数据，这时会返回解析失败的3840信息，如果这时想获取自己去解析不需要返回json数据，那么就需要改变默认的解析方式，这时关键问题如下：
原来响应序列器设置为
AFHTTPResponseSerializer *responseSerializer = [AFJSONResponseSerializer serializer];//此处返回的结果是不可改的；
需要设置为如下才可以：
AFHTTPResponseSerializer *responseSerializer = [AFJSONResponseSerializer serializerWithReadingOptions: NSJSONReadingMutableContainers];//允许返回的结果可改。

+ (void)initialize{

manager=[AFHTTPSessionManager manager];

manager.responseSerializer.acceptableContentTypes=[manager.responseSerializer.acceptableContentTypes setByAddingObjectsFromArray:@[@"text/plain",@"text/html",@"application/json",@"multipart/form-data"]];

manager.requestSerializer = [AFJSONRequestSerializer serializer];
manager.responseSerializer = [AFJSONResponseSerializer serializerWithReadingOptions:NSJSONReadingMutableContainers];//允许返回的结果可改
}

+ (void)GET:(NSString *)urlStr parameters:(id)parameters
success:(void (^)(id responseObject))success
failure:(void (^)(NSError *error))failure {

[manager GET:urlStr parameters:parameters progress:^(NSProgress * _Nonnull downloadProgress) {

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

success(responseObject);

} failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {
//        NSError *underError = error.userInfo[@"NSUnderlyingError"];
//
//        NSData *data=underError.userInfo[AFNetworkingOperationFailingURLResponseDataErrorKey];
//
//        NSString *str = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
//        NSLog(@"%@",str);

NSData *data = error.userInfo[AFNetworkingOperationFailingURLResponseDataErrorKey];
if (data != nil) {
//            id body = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableContainers error:nil];
NSString *str = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(@"error--%@", str); //就可以获取到错误时返回的body信息。
}

failure(error);

}];
}

如下图所示：



http://www.oschina.net/question/2296401_225963

http://www.fx114.net/qa-227-152024.aspx

http://www.jianshu.com/p/03bf22adaf11