control to make an input control a mandatory field.
The input control fails validation if the value it contains does not change from its initial value when validation is performed.
So lets attach a basic Required Field Validator control to this Drop Down List since we want to make sure a value has been specified: This validator displays an * next to the control itself and the error message is getting piped over to a Validator Summary control (not shown).
So the basic Drop Down List looks like this: One quick note, which I had discovered along the way.
The Append Data Bound Items property will take any statically created List Items you have in the control and bind them to the Drop Down List before your databound elements are added.
Sometimes, you will want to have an initial value that is not an empty string.
This is useful when you have a default value for an input control and want the user to select a different value.