title: Web User Controls and Validation
body: <p>I have an ASP.Net web user control that contains a TextBox and a calendar from the Ajax Control Toolkit.</p>
  
  <p>When I include this user control on my page I would like it to participate in input validation (there is a required filed validator set on the TextBox inside the UC), ie. when the page is validated the content of the UC should also be validated. So I had my UC implement the IValidator interface, which worked well except that I could not set the validation group on the user control. Apparently I'm supposed to inherit from BaseValidator to do that, but I can't since I'm already inheriting UserControl.</p>
  
  <p>There's got to be a way to deal with this common scenario.</p>