field validation on Form

On Form Sales Header, on “Sell-to Customer No.” I fixed one customer number, EX: “Sell-to Customer No.”= ‘001’. This customer exists on my Table Customer.

With this I pretend:

When I create a new sales header, my “Sell-to Customer No.” is filled with 001, but all information related to my customer is not flled in my sales header!

How can I do That?

Thanks

Go to the Sales Header Table & view the code OnValidate of the “Sell-To Customer No.” for more info.