The ValueChanged event is fired every time when the user changes the value in the NumericUpDown, even if the focus is still in the control. Alternately, you can try to use the PreviewTextInput
event which is fired every time the user types into the TextBox of the NumericUpDown before the ValueChanged event.
If you still experience difficulties could you please send us your project in order to track down the source of the problem.
the Telerik team
Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Public Issue Tracking
system and vote to affect the priority of the items