实现跨线程访问UI控件的3种方法

namespace 多线程  
{  
    public partial class Form2 : Form  
    {  
        public Form2()  
        {  
            InitializeComponent();  
        }  
  
  
        private void Form2_Load(object sender, EventArgs e)  
        {  
            //1.New 一个thread.  
            //给新创建的thread绑一个带参的方法ParameterizedThreadStart  
            new Thread((ParameterizedThreadStart)(Dosomething)).Start();  
            //如果绑的是无参的方法，就用ThreadStart  
            //new Thread((ThreadStart)(Dosomething)).Start();  
  
  
            //2.在线程池里面做.  
            ThreadPool.QueueUserWorkItem(new WaitCallback(Dosomething));  
  
  
            //3.用backgroundworker  
            using (BackgroundWorker bw = new BackgroundWorker())  
            {  
                bw.DoWork += new DoWorkEventHandler(bw_DoWork);  
                bw.RunWorkerAsync();  
            }  
        }  
  
  
        private void bw_DoWork(object sender, DoWorkEventArgs e)  
        {  
            Dosomething("");  
        }  
  
  
        private void Dosomething(object o)  
        {  
            var text = "跨线程设值";  
            UpdateTextboxText(text);  
        }  
  
  
        private void UpdateTextboxText(string text)  
        {  
            if (this.InvokeRequired)  
            {  
                //this.Invoke((EventHandler)(SetText),new object[] {text});  
                //this.Invoke((MethodInvoker)(delegate { textBox1.Text = text; }));                  
                this.Invoke((Action)( delegate {UpdateTextboxText(text);}));  
                //其中Action,MethodInvoker,Func<>,EventHandler都是系统定义好的委托类型  
            }  
            else  
            {  
                textBox1.Text = text;  
            }  
        }  
    }  
}