Facebook API 正在检索 swift 中的好友列表

Facebook API retrieving friends list in swift

为什么这会给我一个错误?

fatal error: unexpectedly found nil while unwrapping an Optional value

我是不是用错了valueForKeyString?我想获取好友列表。 (有朋友因为当我打印结果时它显示了他们)

let fbRequest = FBSDKGraphRequest(graphPath:"/me/friends", parameters: nil);
fbRequest.startWithCompletionHandler { (connection : FBSDKGraphRequestConnection!, result : AnyObject!, error : NSError!) -> Void in

    if error == nil {
            let userName : NSArray = result.valueForKey("name") as! NSArray
        print("Friends are : \(result)")

    } else {

        print("Error Getting Friends \(error)");

    }
    }

试试这个

let fbRequest = FBSDKGraphRequest(graphPath:"/me/friends", parameters: nil);
fbRequest.startWithCompletionHandler { (connection : FBSDKGraphRequestConnection!, result : AnyObject!, error : NSError!) -> Void in

    if error == nil {
       if let userNameArray : NSArray = result.valueForKey("data") as! NSArray
       {
          var i:Int = 0
          for i;i<userNameArray.count ; i++
          {
             print(userNameArray[i].valueForKey("name"))
          }      

       } else {

        print("Error Getting Friends \(error)");

      }
    }