Prevent resubmit form after click “back” button

Question

I have 2 pages :

page1.php :
- has a form with text box and a \"submit\" button. Eg :

Answer 1

You can prevent the re-submission by implementing the Post-Redirect-Get (PRG Pattern).

Could be just a one-line if you've got the http_redirect function:

http_redirect("page2.php");

Instead of your javascript echo.

If not, that are two lines:

header("Location: http://example.com/page2.php");
exit;

Replace example.com with site's your hostname.

Related: Back button re-submit form data ($_POST); I am confused about PHP Post/Redirect/Get