Marks a program entity that should not be used.

[Obsolete(
   message
)]
[Obsolete(
   message,
   iserror
)]

Parameters

message

A string; ideally, a human-readable explanation of why the item is obsolete and what to use instead.

iserror

A bool; if true, the compiler should treat the use of the item as an error. Default value is false (compiler generates a warning).

Applies To

Any declaration that allows attributes.

Remarks

The Obsolete attribute is a single-use attribute. Obsolete is an alias for System.ObsoleteAttribute.

When an entity marked Obsolete is used in a program, the compiler issues either an error or a warning (depending on iserror) and prints out message.

Example

// cs_attribute_obsolete.cs
// CS0619 expected
using System;
public class MyClass 
{
   [Obsolete("Don't use OldWay; use NewWay instead", true)]
   static void OldWay( ) { Console.WriteLine("Silly me!"); }
   static void NewWay( ) { Console.WriteLine("D'oh!"); }
   public static void Main( ) 
   {
      OldWay( );
   }
}

See Also

C# Attributes