Textbox MouseUp MouseDown events not firing

while working on a Fileupload control for WPF, i noticed that the mouseUp and mouseDown event (ShowDialog in my case) never gets fired...

found on MSDN ,
TextBox has built-in handling for the bubbling MouseUp and events. Custom event handlers that listen for MouseUp or MouseDown events from a TextBox will never be called. If you need to respond to these events, listen for the tunneling PreviewMouseUp and PreviewMouseDown events instead.


http://msdn.microsoft.com/en-us/library/ms750580.aspx