How to know validation has errors programmatically?

Hi There,

For example, in the UIhttp://i.msdn.microsoft.com/ff714593.Noyes_Figure4_small(en-us,MSDN.10).png . if user has inputted any information violating any validation rules, I want sete.CanExecute =False; in CommandBinding.CanExecute Event handler.

 I know how to call Validation.GetHasError Method one by one. I wonder if there is window level function to call once only.

Thanks in advance.

Rulin Hong