ios - 注册时获取可选值崩溃

Question

当我尝试注册时，我得到了正确的回复。但是在获得成功之后。我将崩溃作为可选值。

这是我的完整代码:

   var post:NSString = "name=\(Username)&email=\(Email)&phone=\(phonenumb)&password=\(Password)&address=\(address)"

    NSLog("PostData: %@",post);

    var url:NSURL = NSURL(string: "http://userregistration.php")!
   // let url:NSURL = NSURL(string: "http://userregistration.php")!

    let postData:NSData = post.dataUsingEncoding(NSASCIIStringEncoding)!

    let postLength:NSString = String( postData.length )

    let request:NSMutableURLRequest = NSMutableURLRequest(URL: url)
    request.HTTPMethod = "POST"
    request.HTTPBody = postData
    request.setValue(postLength as String, forHTTPHeaderField: "Content-Length")
    request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
    request.setValue("application/json", forHTTPHeaderField: "Accept")


    let reponseError: NSError?
    var response: NSURLResponse?

    do {
        let urlData = try? NSURLConnection.sendSynchronousRequest(request, returningResponse: &response)

        if ( urlData != nil ) {
            let res = response as! NSHTTPURLResponse!;

            NSLog("Response code: %ld", res.statusCode);

            if (res.statusCode >= 200 && res.statusCode < 300)
            {
                let responseData:NSString  = NSString(data:urlData!, encoding:NSUTF8StringEncoding)!

                NSLog("Response ==> %@", responseData);


                do {
                    let jsonData = try NSJSONSerialization.JSONObjectWithData(urlData!, options: []) as! NSDictionary

                    let success:NSInteger = jsonData.valueForKey("success") as! NSInteger

                    //[jsonData[@"success"] integerValue];

                    NSLog("Success: %ld", success);

                    if(success == 1)
                    {
                        NSLog("Sign Up SUCCESS");
                        //self.dismissViewControllerAnimated(true, completion: nil)
                    } else {
                        var error_msg:NSString

                        if jsonData["error_message"] as? NSString != nil {
                            error_msg = jsonData["error_message"] as! NSString
                        } else {
                            error_msg = "Unknown Error"
                        }
                        let alertView:UIAlertView = UIAlertView()
                        alertView.title = "Sign Up Failed!"
                        alertView.message = error_msg as String
                        alertView.delegate = self
                        alertView.addButtonWithTitle("OK")
                        alertView.show()

                    }

                } catch let error as NSError {
                    print("json error: \(error.localizedDescription)")
                }



            } else {
                let alertView:UIAlertView = UIAlertView()
                alertView.title = "Sign Up Failed!"
                alertView.message = "Connection Failed"
                alertView.delegate = self
                alertView.addButtonWithTitle("OK")
                alertView.show()
            }
        }

    }
}

我在这一行中崩溃了:

 let success:NSInteger = jsonData.valueForKey("success") as! NSInteger

错误是选项值崩溃。我不知道如何处理这个错误。有没有专家给我一些想法或一些解决方案来纠正这个崩溃

Answer 1

始终使用安全解包，并且不要直接尝试解包/转换可以为 nil 的值。

正确的方法是-

if let successVal = jsonData["success"] as? NSInteger {
   //Do something with successVal. 
}

虽然与您的问题没有直接关系，但想指出您使用的是已弃用的 NSURLConnection API，而不是使用基于 NSURLSession 的 API 进行联网。

谢谢