Cast

In this chapter you will learn:

  1. What is up casting
  2. What is down casting

Up casting

Up casting is a cast towards its super class or parent class.

using System;/*j a  va 2 s.c om*/
class Person
{
    public string name;
}
class Employee : Person
{
    public string companyName;
}

class Program
{
    static void Main(string[] args)
    {
        Employee e = new Employee();
        e.name = "java2s.com";


        Person p = e;
        Console.WriteLine(e.name);
        Console.WriteLine(p.name);
       
    }
}

The output:

Down casting

Down cast happens when casting to subclass or child class. Down cast needs an explicit cast.

using System;//from  j a v  a2s .  c  o  m
class Person
{
    public string name;
}
class Employee : Person
{
    public string companyName;
}

class Program
{
    static void Main(string[] args)
    {
        Person p = new Employee();

        Employee e = (Employee)p;
       
    }
}

Next chapter...

What you will learn in the next chapter:

  1. What is member shadow
  2. When to use new and virtual in member shaow
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