Assembly: PresentationFramework (in PresentationFramework.dll)
An evaluated expression will also report the specific base value setting condition where the expression was applied, as a value in BaseValueSource. The BaseValueSource is still very relevant for any property where is true. Knowing whether a value came through an expression can be particularly useful if the value was set indirectly, such as through a template or an inherited property value.
If an expression fails to evaluate (the binding failed; no resource of that name was found), then the value will come from some other participant in the property system, most likely the default value. That source is then reported in BaseValueSource. Failed expression evaluations will return false for .
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.