Validation on DatePicker not work.

Jan 20, 2009 at 4:04 AM
Hi, I have use wpf toolkit DatePicker on my application. I have try to create validation class to check is it value is null or not. But it not working in any manner.
My code in is like below
bindingExpression = datePicker.GetBindingExpression(Microsoft.Windows.Controls.DatePicker.SelectedDateProperty);
bindingExpression.UpdateSource(); // make sure that source is update.
In contrast, I have use to use BagOTrick DatePicker it working as i expect. I want to know, Am I have any missing point ? and How to solving this problem?