我无法捕获此功能的错误 [重复]

Question

我在调用中的八行“extra argument 'error''中遇到错误。有什么建议吗？

@IBAction func loadFollowers(sender: AnyObject) {

    Twitter.sharedInstance().APIClient.sendTwitterRequest(Twitter.sharedInstance().APIClient.URLRequestWithMethod("GET", URL: "https://api.twitter.com/1.1/friends/ids.json", parameters: ["user_id":Twitter.sharedInstance().session()!.userID], error: nil), completion:
        {(response:NSURLResponse?, data:NSData?, error:NSError?) -> Void in

        var dic = NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.AllowFragments, error: nil) as! NSDictionary
        var friends = dic["ids"] as! NSArray
        self.following = friends

            Twitter.sharedInstance().APIClient.sendTwitterRequest(Twitter.sharedInstance().APIClient.URLRequestWithMethod("GET", URL: "https://api.twitter.com/1.1/followers/ids.json", parameters: ["user_id":Twitter.sharedInstance().session()!.userID], error: nil), completion: {(resonse:NSURLResponse?,data:NSData?,error:NSError?) -> Void in

            var dic = NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.AllowFragments, error: nil) as! NSDictionary
            var followers = dic["ids"] as! NSArray
            self.followers = followers
            for id in self.following {
                if !self.followers.containsObject(id)
                {
                    var st = id as! NSNumber
                    Twitter.sharedInstance().APIClient.loadUserWithID(st.stringValue, completion: {(user:TWTRUser?,error:NSError?) -> Void in
                        self.results.addObject(user!)
                        //self.tableView.reloadData()
                        print("done")
                    })
                }
            }

        })
    })}

Answer 1

在 Objective-C 中这曾经是可能的，现在你必须这样做：

do{
  let dict = try NSJSONSerialization.JSONObjectWithData(data!, options: .AllowFragments) as! NSDictionary
}catch let error{
  print(error)
}