C# 0 The Complete Reference

PART I

C h a p t e r   1 7 :  

R u n t i m e   T y p e   I D ,   R e f l e c t i o n ,   a n d   A t t r i b u t e s  

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PART IPART I

The Obsolete Attribute

The

Obsolete

 attribute, which is short for 

System.ObsoleteAttribute

, lets you mark a 

program element as obsolete. It has this general form:

[Obsolete(“

message

”)]

Here, 

message

 is displayed when that program element is compiled. Here is a short example:

// Demonstrate the Obsolete attribute.

using System;

class Test {

  [Obsolete("Use MyMeth2, instead.")]

  public static int MyMeth(int a, int b) {

    return a / b;

  }

  // Improved version of MyMeth.

  public static int MyMeth2(int a, int b) {

    return b == 0 ? 0 : a /b;

  }

  static void Main() {

   // Warning displayed for this.

    Console.WriteLine("4 / 3 is " + Test.MyMeth(4, 3));

   // No warning here.

    Console.WriteLine("4 / 3 is " + Test.MyMeth2(4, 3));

  }

}

When the call to