refresh (back?) causing browser to resubmit form

mrmigu

Hi, Ive got a form on my site where users are registering and paying for a service, which is submitted to a 3rd party site which takes care of the financial aspect and then forwarded to a confirmation screen on my page. It seems as if some users are hitting the back button and resubmitting the data, as they are being registered multiple times.

What would be a good way to get around this, so they could not go back to the page where the form was submitted and therefore re register?

Thanks

bbreslauer

You could open a new browser window, though then there would be issues with what would happen when they close the new window and go back to the register page with all their information still filled in.

You could check to see what the referring page was, and then only accept the submitted form if they came from the correct page. This is what I'd try to do.

There might also be some javascript way to remove the back history, but I wouldn't recommend that either.

mrmigu

what ive done is just redirect them from the page that the 3rd party sends them to, so itll be harder for them to go back, and disabled the submit button upon submission just incase it is a double submit

your 2nd suggestion sounds like it would work in most cases, but unfortunately i have no control over whether or not the 3rd party could check that

jansky

what i did is i unset evertyhing after i post my data

like
if (isset($_POST["Submit"])) // let as assume we click the button SUBMIT
{
// do your stuff here

 unset($_POST);  // clear everything

}

Onurphp

if you use mysql colums you can use Unique Keys.