c# - 文本框的计时器/刷新功能

Question

在我的应用程序中，我有两个带有两个标签的文本框:“已连接”和“未连接”。从我的代码中可以看到，如果建立了连接，则“已连接”文本框将充满绿色，表示网络连接。如果不是，它将为红色。

连接检测的功能运行良好，但是，我必须重新打开应用程序才能检测到更改。我正在寻找一种每5-10秒左右刷新一次应用程序以自动检测连接性变化的方法。我不想清除任何其他字段或框的内容，而仅清除彩色文本框。可以说是一个软轮询循环。我将如何使用Timer方法执行此操作。我应该创建一个新的线程来运行计时器并刷新该框吗？

谢谢。

  if (System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable() == false)
        {
            noConnect.Select();  //if not connected, turn box red
            noConnect.BackColor = Color.Red;

        }

        else
        {
            netConnect.Select();  // if connected, turn box green
            netConnect.BackColor = Color.Lime;

        }

        //need to refresh box/application without losing other box/field contents 
        //in order to constantly check connectivity around 5-10 seconds or so
        //constantly check connectivity 

Answer 1

这样的事情会起作用

    public Form1()
    {
        InitializeComponent();
        var timer = new Timer();
        timer.Tick += new EventHandler(timer_Tick);
        timer.Interval = 10000; //10 seconds
        timer.Start();
    }

    void timer_Tick(object sender, EventArgs e)
    {
        if (your_function_call())
        {
            netConnect.BackColor = Color.Green;
        }
        else
            netConnect.BackColor = Color.Red;
    }

在每个时间间隔都会重复调用timer_Tick，您可以轮询状态并更新控件。由于在UI线程中调用了计时器回调，因此您可以更新任何UI元素。

从 Timer Class

A Timer is used to raise an event at user-defined intervals. This Windows timer is designed for a single-threaded environment where UI threads are used to perform processing. It requires that the user code have a UI message pump available and always operate from the same thread, or marshal the call onto another thread. When you use this timer, use the Tick event to perform a polling operation or to display a splash screen for a specified period of time. Whenever the Enabled property is set to true and the Interval property is greater than zero, the Tick event is raised at intervals based on the Interval property setting.

此解决方案使用 System.Windows.Forms.Timer在UI线程上调用滴答声。如果使用 System.Timers.Timer，则回调将不在UI线程上。