Pull Variables into a form without page refresh

This is a general programming problem which could reside in ASP, PHP or Javascript, but I had to opt for one!

I have a web form and in the address section the user clicks to open a new window, then searches to retrive their address details.

What I then need to do is Post the variables from the new window into the main form, without a page refresh, and thus not loosing all the other entered data.

I have thought of Posting all the form variables to the popup window, then posting them back however the form is long and fairly complex so before I try this I wanted to ask if there was any other ideas for a way around.......?

Look forward to any ideas.
Andy

Sounds like you need the help of AJAX, though I wouldn't know how!

AJAX yes, on my search I have stumbled across that, hhmmm now the big question is how?! lol

I've had this list of AJAX tutorials in my bookmarks for a while now (though never looked at ).

Seems a solid start to getting familiar with AJAX and the XMLHttpRequest Object