AFHTTPRequestOperationManager的那些事

AFHTTPRequestOperationManager *mgr = [AFHTTPRequestOperationManager manager];

// responseObject的类型是NSXMLParser

    mgr.responseSerializer = [AFXMLParserResponseSerializer serializer];

// responseObject的类型是NSData

    mgr.responseSerializer = [AFHTTPResponseSerializer serializer];

//服务器返回的是JSON数据

    mgr.responseSerializer = [AFJSONResponseSerializer serializer];

是要设置的,否则报错.默认JSON.