title: Client-side validation for custom editor templates in MVC4
body: <p>I have a viewModel that contains an object.  I've defined a custom editor template for that object, which allows me to edit each of the children of that object.  The children values aren't required serverside (so I don't have any Required annotations), however if the user reaches this particular input, it should be required.  </p>
  
  <p>Is there any way I can inspect the values of these children objects (within the viewModel) in the POST method, and return some errors to the view if they are null?  </p>
  
  <p>I'm using Razor.</p>