委托操作控件-01

 protected delegate void UpdateControlText(string strText); //定义一个委托  

        //定义更新控件的方法  
        protected void updateControlText(string strText)
        {
            this.label1.Text = strText;
            return;
        }  
        private void button1_Click(object sender, EventArgs e)
        {
            Thread ff = new Thread(new ThreadStart(x1));
            ff.Start();  
        }
        private void x1()//线程安全的访问窗体控件  
        {
            for (int i = 0; i < 1000; i++)
            {
                long xx = Convert.ToInt32(this.label1.Text);
                if (this.InvokeRequired)
                {
                    //用更新控件的方法updateControlText实例化一个委托update  
                    UpdateControlText update = new UpdateControlText(updateControlText);
                    this.Invoke(update, Convert.ToString(++xx));  //调用窗体Invoke方法  
                }
                else
                {
                    this.label1.Text = Convert.ToString(++xx);
                }
            }
        }