I am trying to set up some validation, so that if the \'Yes\' radio button is checked another control, which is a drop down list needs to be validated to ensure it is not se
ScottE is correct. I have a dropdownlist populated from a database and I just appended an item at the very top of the list and gave it a value of "". When you validate the input just validate against the dropdownlist being blank. You could also hard code the list if it never changes and add an item to the top with a blank value, example below.
_example.Add(new SelectListItem { Text = "Select Example", Value = ""});