Occurs when changes occur that affect whether or not the command should execute.
Assembly: System (in System.dll)
Normally, a command source calls CanExecute on the command when this event occurs.
Normally, if the command cannot execute, the command source disables itself.
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.