namespace DelegatesCS
{
using System;
public class Wisdom //包含代理的类
{
public delegate string GiveAdvice();
public string OfferAdvice(GiveAdvice words)
{
return words();
}
}
public class Parent //基类
{
public virtual string Advice()
{
return("Listen to reason");
}
~Parent() {}
}
public class Dad: Parent //子类
{
public Dad() {}
public override string Advice()
{
return("Listen to your Mom");
}
~Dad() {}
}
public class Mom: Parent //子类
{
public Mom() {}
public override string Advice()
{
return("Listen to your Dad");
}
~Mom() {}
}
public class Daughter //不继承与基类的类
{
public Daughter() {}
public string Advice()
{
return("I know all there is to life");
}
~Daughter() {}
}
public class Test
{
public static string CallAdvice(Parent p)//使用基类
{
Wisdom parents = new Wisdom();
Wisdom.GiveAdvice TeenageGirls = new Wisdom.GiveAdvice(p.Advice);//将Advice方法委托给TeenageGirls委托对象
return(parents.OfferAdvice(TeenageGirls));
}
public static void Main()
{
Dad d = new Dad();
Mom m = new Mom();
Daughter g = new Daughter();
//以下两个为衍于基类的类
Console.WriteLine(CallAdvice(d));
Console.WriteLine(CallAdvice(m));
//以下为未衍于基类的类，如果调用将出错。
//Console.WriteLine(CallAdvice(g));
}
}
}
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