Leading Zeros

I have a field labeled itemNo defined as nvarchar 50 in table on sql server.

On the form, when they enter the itemNo, I need it to be 00010, alsways 5 digits with leadgin zeros, because I have to use that as an exact match in a search later on. Most of the time, they only enter 10 and my search fails.

How do I automatically add the leading zeros to the form variable.I suppose I can check for length and insert it with the leading zeros, but I am using the form variable to check, so I would like that to have leading zeros.

Thanks