Featuredatagrid not found

[rawanaisheh]

Dear all,
I'm working on sl5, Arcgis API 3.1, Arcgis server 10, I added  a code from the web samples  for API 3.1

http://resources.arcgis.com/en/help/silverlight-api/samples/start.htm#OrderByFieldQuery

but I always had the error Featuredatagrid not found,  I added the following to the code
xmlns:sldata="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.data" , but still have the same problem.
thanks

[ArtemisFili]

You also need to add the ESRI.ArcGIS.Client.Toolkit reference to the project.

[rawanaisheh]

You also need to add the ESRI.ArcGIS.Client.Toolkit reference to the project.

thanks Artemisfili that solve my problem.