static void BoillingFinishedCallback(IAsyncResult result)
{
AsyncResult asyncResult = (AsyncResult)result;
BoilDelegate d = (BoilDelegate)asyncResult.AsyncDelegate;
Console.WriteLine("烧水共用去{0}时间。", d.EndInvoke(result));
Console.WriteLine("小文：将水灌入壶中。");
Console.WriteLine("小文：继续处理家务...");
}
static void Main(string[] args)
{
Console.WriteLine("小文：将水壶放到火炉上。");
BoilDelegate d = new BoilDelegate(Boil);
IAsyncResult result = d.BeginInvoke(BoillingFinishedCallback, null);
//d.EndInvoke(result);
Console.WriteLine("小文：开始整理家务...");
for (int i = 0; i < 20; i++)
{
Console.WriteLine("小文：整理第{0}项家务...", i);
Thread.Sleep(1000);
}
Console.ReadLine();
}
