ch2_12.cs

《c#技术内幕代码》

using System;
public class Person
{
   private int fAge;
   
   public Person()
   {
      fAge = 21;
   }
   public virtual void setAge(int age)
   {
      fAge = age;
   }
   public virtual int getAge()
   {
      return fAge;
   }
}

public class AdultPerson : Person
{
   public AdultPerson()
   {
   }
   override public void setAge(int age)
   {
      if ( age > 21 )
         base.setAge(age);
   }
}

class CH2_12
{
   public static void Main()
   {
      Person p = new Person();
      p.setAge(18);
      AdultPerson ap = new AdultPerson();
      ap.setAge(18);
      Console.WriteLine("Person Age: {0}", p.getAge());
      Console.WriteLine("AdultPerson Age: {0}", ap.getAge());
   }
}