C#面试笔试小贴士 2

对于多态，还必需提一个C#中的关键字：new。前面提到，对于virtual方法，JIT会确定实例的实际类型然后决定调用什么方法。但是如果派生类中new关键字修饰方法，则它向CLR澄清此派生类中的方法与基类中的方法毫无关系，以下代码最终调用是基类的introduce方法：
Code
class Program
{
    static void Main(string[] args)
     {
         Sample1.M1(new OrdinaryPeople("ZhangSan"));
         Sample1.M1(new Superman("Hancock"));
         Console.Read();
     }
}
class Sample1
{
    public static void M1(Person p)
     {
         p.Introdce();
     }
}
class Person
{
    protected string mName;
    public Person(string pName)
     {
        this.mName = pName;
     }
    public virtual void Introdce()
     {
         Console.WriteLine("Hello,I am " + this.mName);
     }
}
class OrdinaryPeople : Person
{
    public OrdinaryPeople(string pName)
         : base(pName)
     {
     }
    public new void Introdce()
     {
         Console.WriteLine("Hello,I am an ordinary person," + this.mName);
     }
}
class Superman : Person
{
    public Superman(string pName)
         : base(pName)
     {
     }
    public new void Introdce()
   &