static void Main(string[] args)
{
 //委托异步
 Action<string> showMessage = ShowMessage;
 IAsyncResult result = showMessage.BeginInvoke(\"测试异步委托\",null, null);
 //那在异步线程未完成工作以前主线程将处于阻塞状态
 //等到异步线程结束，主线程才能继续工作
 showMessage.EndInvoke(result);
 Console.ReadLine();
}
static void ShowMessage(string x)
{
 string current = string.Format(\"当前线程id为{0}\",Thread.CurrentThread.ManagedThreadId);
 Thread.Sleep(1000);
 Console.WriteLine(string.Format(\"{0},输入为{1}\", current, x));
}