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RequiredRuntimeAttribute Class

Defines the metadata attribute that task authors use to identify whether the task requires a specific version of the CLR runtime.

Namespace:  Microsoft.Build.Framework
Assembly:  Microsoft.Build.Framework (in Microsoft.Build.Framework.dll)

[AttributeUsageAttribute(AttributeTargets.Class, AllowMultiple = false, Inherited = false)]
public sealed class RequiredRuntimeAttribute : Attribute

A task marked with the RequiredRuntimeAttribute indicates that it has a stricter runtime requirement than a regular task. It alerts MSBuild that it may need to start a separate process for the task if the current CLR runtime version does not match the required version.


This attribute is currently non-functional because only one version of the CLR (2.0) is capable of running either MSBuild version 2.0 or 3.5.

For more information about using attributes, see Extending Metadata Using Attributes.


Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5