无法使用类型为“（with：NSData，选项：JSONSerialization.ReadingOptions，错误：inout NSError？）”的参数列表调用“jsonObject”？）

Question

我是一名新的 iOS 开发新手，仍在从 YouTube 学习或阅读一些有关 swift 的电子书等。

实际上，我正在关注 YouTube 上的本教程iOS 登录和注册屏幕教程，了解如何使用 JSON 数据创建 iOS 登录和注册，但我认为该代码在带有 Xcode 8 的 swift 3 中效果不佳。我有一些问题/错误，我现在无法解决问题，我已经用谷歌搜索过了，但我不知道如何解决这个问题。

这是我的 LoginVC.swift 文件中的屏幕截图

这是 LoginVC.swift 中的所有代码

import UIKit

class LoginVC: UIViewController {

    @IBOutlet weak var txtUsername: UITextField!
    @IBOutlet weak var txtPassword: UITextField!
    
    
    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    
    @IBAction func btnLoginTapped(_ sender: UIButton) {
        // let userName = txtUsername.text;
        // let userPassword = txtPassword.text;
        
        let username = txtUsername.text
        let password = txtPassword.text
        
        if ( username!.isEqual("") || password!.isEqual("") ) {
            
            var alertView:UIAlertView = UIAlertView()
            alertView.title = "Sign in Failed!"
            alertView.message = "Please enter Username and Password"
            alertView.delegate = self
            alertView.addButton(withTitle: "OK")
            alertView.show()
        } else {
            
            var post:NSString = "username=\(username)&password=\(password)" as NSString
            
            NSLog("PostData: %@",post);
            
            var url:NSURL = NSURL(string:"http://192.168.1.17/userAPI/api/users")!
            
            var postData:NSData = post.data(using: String.Encoding.ascii.rawValue)! as NSData
            
            var postLength:NSString = String( postData.length ) as NSString
            
            var request:NSMutableURLRequest = NSMutableURLRequest(url: url as URL)
            request.httpMethod = "POST"
            request.httpBody = postData as Data
            request.setValue(postLength as String, forHTTPHeaderField: "Content-Length")
            request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
            request.setValue("application/json", forHTTPHeaderField: "Accept")
            
            
            var reponseError: NSError?
            var response: URLResponse?
            
            var urlData: NSData? = NSURLConnection.sendSynchronousRequest(request, returningResponse:&response, error: &reponseError)
            
            if ( urlData != nil ) {
                let res = response as! HTTPURLResponse!;
                // let dict: [String: Any] = ["key": value]
                NSLog("Response code: %ld", res?.statusCode ?? <#default value#>);
                
                if ((res?.statusCode)! >= 200 && (res?.statusCode)! < 300) {
                    var responseData:NSString  = NSString(data:urlData! as Data, encoding:String.Encoding.utf8.rawValue)!
                    
                    NSLog("Response ==> %@", responseData);
                    
                    var error: NSError?
                    
                    let jsonData:NSDictionary = JSONSerialization.jsonObject(with: urlData!, options: JSONSerialization.ReadingOptions.mutableContainers, error: &error) as! NSDictionary
                    
                    // let jsonData:NSDictionary = JSONSerialization.JSONObjectWithData(urlData!, options:JSONSerialization.ReadingOptions.MutableContainers , error: &error) as! NSDictionary
                    
                    let success:NSInteger = jsonData.value(forKey: "success") as! NSInteger
                    
                    //[jsonData[@"success"] integerValue];
                    
                    NSLog("Success: %ld", success);
                    
                    if(success == 1) {
                        NSLog("Login SUCCESS");
                        
                        var prefs:UserDefaults = UserDefaults.standard
                        prefs.set(username, forKey: "USERNAME")
                        prefs.set(1, forKey: "ISLOGGEDIN")
                        prefs.synchronize()
                        
                        self.dismiss(animated: 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"
                        }
                        var alertView:UIAlertView = UIAlertView()
                        alertView.title = "Sign in Failed!"
                        alertView.message = error_msg as String
                        alertView.delegate = self
                        alertView.addButton(withTitle: "OK")
                        alertView.show()
                        
                    }
                    
                } else {
                    var alertView:UIAlertView = UIAlertView()
                    alertView.title = "Sign in Failed!"
                    alertView.message = "Connection Failed"
                    alertView.delegate = self
                    alertView.addButton(withTitle: "OK")
                    alertView.show()
                }
            } else {
                var alertView:UIAlertView = UIAlertView()
                alertView.title = "Sign in Failed!"
                alertView.message = "Connection Failure"
                if let error = reponseError {
                    alertView.message = (error.localizedDescription)
                }
                alertView.delegate = self
                alertView.addButton(withTitle: "OK")
                alertView.show()
            }
        }
        
        
    }
    
    func textFieldShouldReturn(textField: UITextField) -> Bool
    {   //delegate method
        textField.resignFirstResponder()
        return true
    }

} 

错误实际上在这些行上：

var urlData: NSData? = NSURLConnection.sendSynchronousRequest(request, returningResponse:&response, error: &reponseError)

NSLog("Response code: %ld", res?.statusCode ?? <#default value#>);

let jsonData:NSDictionary = JSONSerialization.jsonObject(with: urlData!, options: JSONSerialization.ReadingOptions.mutableContainers, error: &error) as! NSDictionary

我有点卡住了，很困惑如何解决这个问题。

有人可以帮忙解决这个问题吗？我真的很感激。或者有人可以告诉我如何使用 Swift3 中的 API 学习和创建登录屏幕？

Answer 1

这是因为我们在获取数据时没有处理错误。因此我们需要安全地输入种姓数据，然后将其传递给 JsonSerializer。这是代码。

        do {
            let data = try NSData.init(contentsOfFile: path) as Data
            let jsonArray = try JSONSerialization.jsonObject(with: data, options: .mutableContainers)
            print(jsonArray)
        } catch {

        }