Using session variables to maintain form data during a browser back sequence

I have a multipage form, with back buttons, and I'm trying to have a server-side way to maintain the form data if the user clicks back.

I have a back button like this:

<button id="backButton">Back</button>

And the button handler is as such:

$('#backButton').live('click',function() {
        window.history.back();
    });

After the first part of the form is submitted, I put all of the submitted data into $_SESSION variables. I can even echo o开发者_如何学Cut those variables on the second part of the form, but when I click the back button to go to the first part of the form, the session variables don't carry over.

I am starting the session correctly and I use session variables for various other parts of the site, and they work flawlessly.

How can I carry variables back when a back button is pressed?

Sennheiser, I can't get a handle on your exact situation, but I can get your problem. Here are my thoughts:

1. When the user hits 'back', they usually load the page from the browser cache. Ergo, the browser is not asking PHP to re-parse the page with the session variables. Try hitting shift or Control F5 to re-request the page from the server.
2. #1 being successful or not is irrelevant, since no user is going to refresh the page thinking their results will return. You have to rely upon the browser OR JavaScript.
3. A brief review, looking this up, makes me think the following solutions are your best bet:

You can either..

• Use JavaScript to retrieve the form data and save the contents to a cookie, which will be loaded (Safely!! Look out for XSS..) whenever the form is loaded. You seem to use jQuery, that'll help! I'm unsure of the safety, but read up on $.('#formID').serialize().

• Rely upon the browser's native form-saving components. While doing a review of stack overflow, I found a similar question that had an answer that can help you. In summation, if your forms are automatically generated by JS or the page is non-cacheable (likely https, or your server says no-cache), you cannot rely upon the browser to save the form.

Let me know if my answers helped.

#1 of SoreThumb's answer is what I suggested might be happening in my comment.

But if that is the case, it's certainly not irrelevant.

You can tell the browser not to cache it when it is first loaded.

See this related question, this tutorial and this thread.