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;
}
}
}
}