static void Main(string[] args)
{
Boyfriend bf = new Boyfriend("贝贝", 20160512);
Father father = new Father("老晶", 19800101);
bf.printInfo();
father.printInfo();
People p = new People("欢欢");
p.printInfo();
Console.WriteLine("");
p = bf; // 可以兼容特殊化的 People 类——Boyfriend 类
p.printInfo(); // 运行时多态
p = father;
p.printInfo(); // 运行时多态
Console.WriteLine("");
People.show(bf);
People.show(father);
Console.ReadLine();
}
public static void show(People p)
{
p.printInfo();
}
