使用BeginInvoke,EndInvoke异步调用委托

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading;

  

namespace ConsoleApplication1

{

    class Program

    {

        static void Main(string[] args)

        {

            Console.WriteLine("Main ThreadId = " + Thread.CurrentThread.ManagedThreadId);

            //给委托赋值

            Func<long, long> delegateMethod = new Func<long, long>(CalcSum);

            //异步执行委托,这里把委托本身作为asyncState对象传进去，在回调函数中需要使用委托的EndInvoke来获得结果

            delegateMethod.BeginInvoke(200, DoneCallback, delegateMethod);

            //异步执行委托,抛出异常

            delegateMethod.BeginInvoke(10000000000, DoneCallback, delegateMethod);

            Console.ReadLine();

        }

  

        //委托回调函数

        static void DoneCallback(IAsyncResult asyncResult)

        {

            //到这儿委托已经在异步线程中执行完毕

            Console.WriteLine("DoneCallback ThreadId = " + Thread.CurrentThread.ManagedThreadId);

  

            Func<long, long> method = (Func<long, long>)asyncResult.AsyncState;

            //委托执行的异常会在EndInvoke时抛出来

            try {

                //使用BeginInvoke时传入委托的EndInvoke获得计算结果，这时候计算结果已经出来了，有异常的话也在这儿抛出来

                long sum = method.EndInvoke(asyncResult);

                Console.WriteLine("sum = {0}",sum);

            }

            catch (OverflowException)

            {

                Console.WriteLine("运算溢出了");

            }

        }

  

        //委托方法

        static long CalcSum(long topLimit)

        {

            //委托在另一个线程中开始执行

            Console.WriteLine("Calc ThreadId = " + Thread.CurrentThread.ManagedThreadId);

            checked

            {

                long result = 0;

                for (long i = 0; i < topLimit; i++)

                {

                    result += i;

                }

                return result;

            }

        }

    }

  

}