直接使用
NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:urlstr]];
AFJSONRequestOperation *operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:request success:^(NSURLRequest *request, NSHTTPURLResponse *response, id JSON) {
} failure:^(NSURLRequest *request, NSHTTPURLResponse *response,NSError *error, id JSON) {
NSLog(@"error:%@,response:%@",error,response);
}];
[operation start];