Dreamweaver

Specify an invalid value

You can specify a value that will register as invalid if the user selects a menu item that is associated with that value. For example, if you specify -1 as an invalid value, and you assign the value to an option tag, the widget will return an error message if the user selects that menu item.

<option value="-1"> ------------------- </option>
  1. Select a Validation Select widget in the Document window.
  2. In the Property inspector (Window > Properties), enter a number to use as in invalid value in the Invalid Value box.