RadInput supports client and server-side ASP.NET validation. This
example shows how to use RequiredFieldValidator, RangeValidator
and RegularExpressionValudator with RadNumericTextBox,
RadTextBox, RadDateInput and RadMaskedTextBox.
All you need to do is set the ControlToValidate property of your
validator to point to the respective input instance.
Type some data in the input controls then press the submit button. ASP.NET validation
would fail in case of invalid or missing data.