VB.Net -  I've got a drop down where the first item says "Please Select" in
the text of the drop down and 0 as the value for that item. I've also got a
text box that after you select the drop down item, there needs to be a value
typed into the text box. So, if there is an item selected in the drop down
listbox (other than zero), then the textbox must have a value.

I know I can just write javascript and check each field by writing a
javascript routine to be called when the submit button is clicked, or I can
bounce the page and check it there, but I would like to use a required field
validator. Is there a way to use a required field validator (or any other
validator) to check two fields to be required?

Take a look at http://codeproject.com/aspnet/MultiDependValidator.asp

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