Prevent from Submitting Again

All,
I am submitting a form to a page and when I refresh it I want to now allow it to to submit again. I know I get a pop up box and I can control the query part by setting a variable in getting the post variables but just curious if PHP had an easier way to do this to find it a page was submitted.

Thanks in advance.

if you are using if php ($_POST) use header to redirect you back to your page - just guessing without seing the code

header("Location: ./yourpage.php");

?php if ($_POST) {echo "Form was entered correctly";} ?>

Set a SESSION variable ...

and check it each time before you display the form.

Google: PHP SESSION TUTORIAL