public delegate int AddHandler(int a, int b); public class JiaFa { public static int Add(int a, int b) { Console.WriteLine("开始计算：" + a + "+" + b); Thread.Sleep(3000); Console.WriteLine("计算完成"); return a + b; } }

同步调用

 static void Main1(string[] args) { //方式1 AddHandler handler = new AddHandler(JiaFa.Add); var res = handler.Invoke(3, 5); Console.WriteLine("继续做其他事情"); Console.WriteLine(res); //方式2 //AddHandler handler2 = new AddHandler((int a, int b) => //{ // Console.WriteLine("开始计算：" + a + "+" + b); // Thread.Sleep(3000); // Console.WriteLine("计算完成"); // return a + b; //}); //Console.WriteLine(handler2(3, 5)); Console.ReadKey(); }

异步调用

 static void Main2(string[] args) { AddHandler handler = new AddHandler(JiaFa.Add); IAsyncResult result = handler.BeginInvoke(3, 5, null, null); Console.WriteLine("继续做其他事情1"); //当主线程执行到EndInvoke时，如子线程还没有执行完，则主线程还是需要等待 Console.WriteLine(handler.EndInvoke(result)); Console.WriteLine("继续做其他事情2"); Console.ReadKey(); }

异步回调

 static void Main(string[] args) { AddHandler handler = new AddHandler(JiaFa.Add); IAsyncResult result = handler.BeginInvoke(3, 5, new AsyncCallback(Call), "AsycState:OK"); Console.WriteLine("继续做其他事情"); Console.ReadKey(); } static void Call(IAsyncResult result) { AddHandler handler = (AddHandler)((AsyncResult)result).AsyncDelegate; Console.WriteLine(handler.EndInvoke(result)); Console.WriteLine(result.AsyncState); }