AJAX and Back Buttons

cmcneal

I have an HTML form that has 2 parts to it. The first part has a category and subcategory dropdown box. The category dropdown box will update the dropdown list in the subcategory dropdown box depending on the choice. Also, there is a <span></span> further down that would show different sets of fields depending on the category as well.

I use PHP to process the response and go to a different page. If I hit the back button then, the <span></span> portion of the form disappears from the screen and would require to resend AJAX request manually (refresh button) to retrieve the <span> fields.

Is there a way to ensure that those fields and their values are preserved during a backbutton click? I tried PHP Session but could not clearly link/pass variables from AJAX to PHP and vice-versa. An example would be appreciated.

big_nerd

I am on my way to work and don't have time to try it.. but have you thought of client side cookies?

leatherback

Ehm.. If you perform your ajax call, in the php page just set the $_SESSION[''] variables for the choices required. When the page loads, you verify these values.

What have you tried?

cmcneal

After pondering on leatherback's response, I have realized that the $_SESSION variable is set while processing the AJAX request at the PHP level and not at the AJAX response phase (duh-uh).

Also, I have gotten around the repagination by actually making all the parts that were supposed to be downloaded from the server as static HTML enclosed in <div></div> where a style to control display is set to either "block" or "none" depending on the "submit" button and the content of the $_POST.

In general, I guess the technique that worked for me is to expire the page and force to refresh the page when the back button is pressed and with the method described above will always ensure that the page is painted correctly.

Thanks a lot.