namespace testThreadAndDelegate 
{ 
    public partial class Form1 : Form
    {
        // 申明委托
        public EventHandler<MyEventArgs> ChangeLabel;
        public Form1()
        {
            InitializeComponent();
            ChangeLabel = new EventHandler<MyEventArgs>(onChangeLabel); // 委托
        }
        // 委托方法
        private void onChangeLabel(object sender, MyEventArgs e)
        {
            this.label1.Text = e.Text;
        }
        private void Form1_Load(object sender, EventArgs e)
        {
            new Thread(new ThreadStart(new Thtest(this).ThreadProc)).Start();             
        }
    }

    public class Thtest
    {
        private Form1 form;
        public Thtest(Form1 form)
        {
            this.form = form;
        }

        public void ThreadProc() 
        { 
            Thread.Sleep(1000); 
            //更新Form1上面的Label的值。 
              //Form1.Label1.Text=System.DateTime.now.tostring(); 
            // 调用委托
            form.Invoke(form.ChangeLabel, new object[] { null, new MyEventArgs(System.DateTime.Now.ToString()) });
            ThreadProc(); 
        } 
    }

    // 委托参数
    public class MyEventArgs : EventArgs
    {
        private String text;
        public MyEventArgs(String text)
        {
            this.text = text;
        }

        public String Text
        {
            get { return text; }
        }
    }
}