How to use XmlPeek task?

I've read in the MSDN MSBuild Task Reference about XmlPeek task at http://msdn.mi开发者_如何学JAVAcrosoft.com/en-us/library/ff598684(v=VS.100).aspx but I cannot use it in my MSBuild script. If you have used this before, please show me how!

The XmlPeek task is only available in MSBuild for .NET 4. So you need to use MSBuild v4.0 and specify in your msbuild file the tool version you are using.

Here a sample project file, where we are looking for the message node.

  <Target Name="TestXmlPeek">
    <XmlPeek Namespaces="&lt;Namespace Prefix='msb' Uri='http://schemas.microsoft.com/developer/msbuild/2003'/&gt;"
             XmlInputPath="$(MSBuildProjectFile)" 
             Query="/msb:Project/msb:Target[@Name='TestXmlPeek']/msb:Message">
      <Output TaskParameter="Result" ItemName="Peeked" />
    </XmlPeek>

    <Message Text="@(Peeked)"/>
  </Target>
</Project>