C#中异步回调函数演示源码

把代码过程经常用的内容做个珍藏，如下代码是关于C#中异步回调函数演示的代码，应该是对大伙有些用途。

static void Main(string[] args)
{
    Func<string,string> showMessage = ShowMessage;
    IAsyncResult result = showMessage.BeginInvoke("测试异步委托", new AsyncCallback(Completed), null);
    while(!result.IsCompleted)
    {
        Console.WriteLine("主线程可以进行其它的操作！");
    }
    Console.ReadLine();

}
static string ShowMessage(string x)
{
    string current = string.Format("当前线程id为{0}",Thread.CurrentThread.ManagedThreadId);
    Thread.Sleep(3000);
    return string.Format("{0},输入为{1}", current, x);

}
static void Completed(IAsyncResult result)
{
    Console.WriteLine("异步完成！");
    AsyncResult _result = (AsyncResult) result;
    Func<string, string> showMessage = (Func<string, string>) _result.AsyncDelegate;
    Console.WriteLine(showMessage.EndInvoke(_result));
}