C#定时器出现错误的问题

[ccbbcc]

代码：

using System;
using System.Windows.Forms;

public class TimerExampleForm : Form
{
    private Timer timer;
    private int counter = 0;
    private Label label;

    public TimerExampleForm()
    {
        // 初始化Label控件  
        label = new Label();
        label.Location = new System.Drawing.Point(50, 50);
        label.Size = new System.Drawing.Size(200, 30);
        this.Controls.Add(label);

        // 初始化Timer控件  
        timer = new Timer();
        timer.Interval = 1000; // 设置时间间隔为1000毫秒（1秒）  
        timer.Tick += new EventHandler(OnTimedEvent);
        timer.Start(); // 启动定时器  
    }

    private void OnTimedEvent(Object myObject, EventArgs myEventArgs)
    {
        // 在这里编写定时执行的代码  
        counter++;
        label.Text = "Counter: " + counter.ToString();
    }

    [STAThread]
    static void Main()
    {
        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        Application.Run(new TimerExampleForm());
    }
}

 

Timer下面有波浪线，该如何解决？谢谢