/*
C#: The Complete Reference
by Herbert Schildt
Publisher: Osborne/McGraw-Hill (March 8, 2002)
ISBN: 0072134852
*/
// Use is to avoid an invalid cast.
using System;
class A {}
class B : A {}
public class CheckCast {
public static void Main() {
A a = new A();
B b = new B();
// Check to see if a can be cast to B.
if(a is B) // if so, do the cast
b = (B) a;
else // if not, skip the cast
b = null;
if(b==null)
Console.WriteLine("Cast b = (B) a is NOT allowed.");
else
Console.WriteLine("Cast b = (B) a is allowed");
}
}
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