c# - Validation.GetHasError always return true for WPF ValidationRule -

I saw a good solution to check the validity of the group of contrÃ'ls:

In my window. Xaml.cs:

  Private bool ISValid (Dependency Object OBJE) {// dependency object is valid if there is no error in it, // and all your children (which are dependent items ) Are error-free! Validation Gethas Error (OBJ) & amp; Amp; LogicalTreeHelper.GetChildren (obj). OFTIP & lt; DependencyObject & gt; (). All (Children => IsValid (Children)); }   
 My problem is, in my case, even if I get an error, then the VID is always right back. I think a xaml mistake The reason is ... but?  
  My windows XAM is:   
  & lt; window. Resources & gt; & Lt; Commandbinding X: key = "binding" command = "save" execution = "save save" CanExecute = "Save_CanExecute" /> & Lt; /Window.Resources> & Lt; Text box name = "Type textbox" grid. Column = "1" vertical alignment = "center" height = "20" & gt; & Lt; TextBox.Text & gt; & Lt; Binding Path = "Styvert Type" & gt; & Lt; Binding.ValidationRules & gt; & Lt; Exceptional Rule / & gt; & Lt; /Binding.ValidationRules> & Lt; / Binding & gt; & Lt; /TextBox.Text> & Lt; / Text box & gt; & Lt; Button template = "{static resource boton reso test}" command = "save" & gt; & Lt; Button.CommandBinding & gt; & Lt; Static Resource Resources = "Binding" & gt; & Lt; / Static Resources & gt; & Lt; /Button.CommandBindings> & Lt; Image Source = "toolbar_wallassar png" height = "16" /> & Lt; / Button & gt;   
  And here my class is C::   
  Private string m_strEvtType; Public string strEvtType {get {return m_strEvtType; } Set {m_strEvtType = value; If (m_objEvtCode.ReadEvtTypebyType (m_strEvtType)! = 0) {New ApplicationExation (M_StrevetTipTRIM) + "lies!"); } FirePropertyChangedEvent ("strEvtType"); FirePropertyChangedEvent ("m_objEvtCode.strDes"); }}   
 Do you know why the validity is always correct?  
 Thanks a lot :)  
 The best regard is :)   
 
 
 I think the problem is  all  use in your  Linq   
 
 All the truths will return if the source specifies each element of the sequence The predicate, passes the test in  or if the sequence is empty ; Otherwise, wrong.                   return! To check Validation.GetHasError (obj), try using other Linq method like  Any . ) And amp; Amp; ! LogicalTreeHelper.GetChildren (obj). OFTIP & lt; DependencyObject & gt; (). Any (child => IsValid (child));