php browser back after post
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I have php page where I used a form to submit messaage. It submits to itself :
action="<? php echo $_SERVER['PHP_SELF'];?>"

Then it sends email, and I have a javascript function that uses jnotify, to alert whether message is sent successfully or not. This function checks if php variable $sent=='yes' then notify about sucessful message else notify about error.

The problem is that when user sends message and goes to another page and comes back by using browsers back button, it is displaying notification. I want it to show notification once only and forget about notification when browsers back or refresh used.

What is the best solution for it?