RE: Re[5]: [PHP-WIN] Preventing multiple submits

Folks, Please ignore my previous email about my feeble attempts to track the multiple submitting of a form using PHP. I have accomplished this via writing a variable to a text file and then reading this in each time and incrementing it, etc. If the value is greater than 1 then the form has already been submitted. I can check for this value each time my PHP script runs and perform the necessary action depending on the value. Of course this is only a temporary solution because it only works in a single user environment. I need to look at sessions and "session_register" in particular it seems! Do the "session" features require that the client can accept cookies? For example, if cookies are disabled on the client do "sessions" still work? Are they server-side only? The whole point of this exercise is to find a server side only solution to preventing a user submitting the same form multiple times. However, I already have the same problem as Pablo, in that the browser only displays the output from the last script ran, which if the user hits the submit button more than once is a message saying "You have already submitted this form" rather than the intended message of "Email has been successfully sent". Is there an easy way to get PHP to immediately clear the screen at the start of a script, without waiting for the rest of the script to finish processing? If so then I can clear the screen immediately after the user clicks the submit button, which would prevent the user from going mad with the submit button! Thanks James -----Original Message----- From: Pablo Vera [mailto:pvz@vercan.com] Sent: 25 August 2000 15:40 To: Zak Greant Cc: James Duncan; php-windows@lists.php.net Subject: Re[5]: [PHP-WIN] Preventing multiple submits Zak: You are COMPLETELY RIGHT !, I did some checking and by registering a variable (with session_register), it will keep its value from script to script. I only have one problem, when the user submitts a second form, the browser will cancel the first connection. The first script will run normally, but its output (confirmation, error, etc.) will not reach the browser. The user will only see whatever the second script sends. If there was an error in the first one, he won't know. How do you solve this ? Saludos, Pablo Vera _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Thursday, August 24, 2000, 5:22:08 PM, you wrote: ZG> At 05:11 PM 8/24/00 -0500, Pablo Vera wrote: >>[snip] >>Zak: >> >>I think that the "if (! $post_counter)" will always result in a true >>condition, this is because the only ways to preserve a variable from >>instance to instance of a script is by sending them in the URL or by >>setting a cookie, but since the form is being submitted twice from >>exactly the same page, you will have two scripts running at the same >>time, with exactly the same variables and values, and the output of >>the first one will not be received by the browser, because the second >>one canceled that connection. You will end up processing two forms, >>but the user will receive confirmation for only one. ZG> The $post_counter variable is not stored client side. All that you store ZG> client side is a session id in either a cookie or as get/post data. ZG> The $post_counter variable is tracked server side by PHP's session manager. ZG> (You could also use another mechanism, if desired.) ZG> - zak