异步委托

using System;
using System.Threading;
using Telerik.WinControls;
using System.Runtime.Remoting.Messaging;

namespace TestForm
{
    public partial class AsyncForm : Telerik.WinControls.UI.RadForm
    {
        public AsyncForm()
        {
            InitializeComponent();
            this.Load += AsyncForm_Load;
        }

        void AsyncForm_Load(object sender, EventArgs e)
        {
            Action<string> ac = SetLabelText;
            ac.BeginInvoke("hahaha", new AsyncCallback(CallBack), "AsyncState:Yes");
        }

        private void CallBack(IAsyncResult ar)
        {
            string str = ar.AsyncState.ToString();//AsyncState:Yes
            Action<string> ac = (Action<string>)((AsyncResult)ar).AsyncDelegate;
            ac.EndInvoke(ar);
        }

        private void SetLabelText(string text)
        {
            Thread.Sleep(2000);
            this.Invoke(new Action(() => {
                radLabel1.Text = text;
            }));
        }
    }
}