WPF: Validating SelectedItem on RadComboBox at the very beginning

[SHING SHUN]

Hi,

I am trying to setup a form that will validate whether a combo box (as well as other inputs) is filled or not.  It seems that the Binding of RadComboBox only happens after PropertyChanged or LostFocus.  What if the input hasn't been touched by the user at all - hence the binding couldn't be triggered?

I can't seems to get it to work.  Please help.

Cheers~

[Vladi]

Hi,

To force the validation before any selection is made in the ComboBox control you could set the SelectedValue when you first load the ViewModel or the control to string.Empty.

Hope this helps.

Greetings,
Vladi
the Telerik team