Get location of all current touches on Windows Phone screen

How do I get the location of all current touches on the phone's screen in a mobile Silverlight a开发者_C百科pplication? The technique described at http://msdn.microsoft.com/en-us/library/ff434208.aspx seems to only apply to XNA applications. Otherwise, it gives the error "The name 'touchPanel' does not exist in the current context".

This article should help you determine all the touchpoints in a Silverlight WP7 Application.

The idea behind is to use TouchPointCollection in Codebehind.