How to Create a Sub-Page
I believe the page I'm creating now will require something I think would be called a sub-page. The main part of the page is connected to either a new or exisitng Purchase Order record and I now need to display either a new item record that is assigned the PO's primary key as a foreign key or exisiting item records that already contain this foreign key. It seems as though I need a new sub-page with its own code-behind loading instructions. I also need a way to pass some data between the main page and the sub-page.
Is there such a capability and, if so, where can I read about how to use it?