.NET Framework Standard Library Annotated Reference, Volume 1: Base Class Library and Extended Numerics Library

Example

using System;

namespace Samples
{
  public class ObsoleteAttributeSample
  {
    [ObsoleteAttribute("Use NewMethod")]
    public static void OldMethod()
    {
      Console.WriteLine("Hi world!");
    }
    public static void NewMethod()
    {
      Console.WriteLine("Hello world!");
    }
    public static void Main()
    {
      OldMethod();
    }
  }
}

An example compile-time result is

 Microsoft (R) Program Maintenance Utility Version 7.00.9466 Copyright (C) Microsoft Corporation. All rights reserved. csc /debug ObsoleteAttribute.cs Microsoft (R) Visual C# .NET Compiler version 7.00.9466 for Microsoft (R) .NET Framework version 1.0.3705 Copyright (C) Microsoft Corporation 2001. All rights reserved. ObsoleteAttribute.cs(18,7): warning CS0618: 'Samples.ObsoleteAttributeSample.OldMethod()' is obsolete: ...