Question

我正在尝试使用Swift从JSON文件中获取值数组。我找到了使用IBAction方法按下按钮时打印值的方法。

函数在第一次按下按钮时正在打印数组但是，如果我再次按下按钮，应用程序崩溃会发出错误：

致命错误：在展开Optional值时意外发现nil （LLDB）

我第一次从打印jsonResult获得的数组看起来像：

1: {
        Age = 30;
        Email = "info@example.com";
        Location = Rome;
        MyText = "Design Agency";
        Name = Admin;
        Password = 123456;
        REF = 002;
        "Reg_Date" = "2015-07-28";
        Sex = Male;
        Surname = "Mobile App"; } 
2: {
        Age = 30;
        Email = "example@gmail.com";
        Location = London;
        MyText = "aaaaaaaaa";
        Name = Andrew;
        Password = 123456;
        REF = 001;
        "Reg_Date" = "2015-07-28";
        Sex = Male;
        Surname = Nos; }

似乎第二次调用该函数时，它无法再读取该文件。我的代码有什么问题？我需要关闭连接吗？

 @IBAction func login_button(sender: AnyObject) {

            searchFunction()
        }

        func searchFunction() {
            var tempUrlValue = loginJsonResults.stringForKey("loginJsonResults")
            let urlPath: String = "https://example.com/iOS/users_result.json"
            var url: NSURL = NSURL(string: urlPath)!
            var request: NSURLRequest = NSURLRequest(URL: url)
            var connection: NSURLConnection = NSURLConnection(request: request, delegate: self, startImmediately: false)!
            connection.start()



        }

        func connection(connection: NSURLConnection!, didReceiveData data: NSData!){
        self.data.appendData(data)
    }

    func connectionDidFinishLoading(connection: NSURLConnection!) {
        var err: NSError
        var jsonResult: NSMutableArray = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: nil) as! NSMutableArray


        //Call jsonResult Values
        var temporaryString: AnyObject = jsonResult[1]

        for (index, jsonResult) in enumerate(jsonResult){
            println("\(index + 1): \(jsonResult)")
            countUsers++
        }
        println(countUsers)
    }

Swift - 尝试第二次获取JSON值时崩溃

0 个答案: