public override void Process(Request request)
{
request.Price *= 0.9;
}
public void TestMethod()
{
IHandler handler1 = new InternalHandler();
IHandler handler2 = new DiscountHandler();
IHandler handler3 = new MailHandler();
IHandler handler4 = new RegularHandler();
//组合链式结构
//internal->mail->discount->retular->null
handler1.Successor = handler3;
handler3.Successor = handler2;
handler2.Successor = handler4;
IHandler head = handler1;
Request request = new Request(20, PurchaseType.Mail);
head.HandleRequest(request);
Console.ReadLine();
}
//需要具体IHandler类型处理的内容 public abstract void Process(Request request);
public override void Process(Request request)
{
}
//按照链式方式依次把调用继续下去
public virtual void HandleRequest(Request request)
{
if (request == null) return;
if (request.Type == Type)
Process(request);
else
if (Successor != null)
successor.HandleRequest(request);
}