The as operator - CSharp Custom Type

CSharp examples for Custom Type:as

  1. HOME
  2. CSharp
  3. Custom Type
  4. as

Introduction

The as operator performs a downcast that evaluates to null rather than throwing an exception if the downcast fails: 

using System;
     public class Item
     {
       public string Name;
     }

     public class Stock : Item   // inherits from Item
     {
       public long SharesOwned;
     }

     public class Company : Item   // inherits from Item
     {
       public decimal Mortgage;
     }
     
     
     class Test
{
static void Main(){
     Item a = new Item();
     Stock s = a as Stock;       // s is null; no exception thrown
}
}

This is useful when you're going to subsequently test whether the result is null: 

if (s != null) 
   Console.WriteLine (s.SharesOwned);

Related Tutorials