How to clear $_POST values?

JediDan · Mar 18, 2004

Hello,
I have a form that submits via POST, which works fine (inserting into a DB). If the user hits Refresh on the page, I would like to not have the data insert a duplicate record. How can I clear the $_POST variables?

unset($_POST) does not work, and I'd rather not have to redirect them to another page just to do this.

Any help is appreciated.

Thanks

LordGarfield · Mar 18, 2004

well if you do something like this.

if (isset($_POST['yourvar'])
{
if ($_POST['yourvar'] != "empty") //empty can be anything
{
// here you do your adding to database stuff
$_POST = "empty";
}
}

tank you,

(>" "<)
(='o'=)
-(,,)-(,,)------------------------------
LORD_GARFIELD
---------------------------------------

apatterno · Mar 19, 2004

If they Reload the page, the browser will send exactly the same POST vars as they sent last time---no matter what you do with the value of $_POST. You can't modify this on the server-side, because the behavior of the browser is beyond your control.

and I'd rather not have to redirect them to another page just to do this

Redirects are very easy, two lines of code. You can actually redirect them right back to the same page.

Code:

<?php
header("Location: [URL unfurl="true"]http://www.server.com/mypage.php");[/URL]
exit;
?>

And to put this into the big picture, your script might look like this (I'm pretending it's a feedback form):

Code:

<?php
    if (isset($_REQUEST['name'] && isset($_REQUEST['email']) && isset($_REQUEST['comments'])) {
         mysql_connect( ... );
         ....             // more MySql related stuff omitted
         mysql_query("INSERT INTO `feedback` (`name`,`email`,`comment`) VALUES('".
            mysql_real_escape_string($_REQUEST['name']."','".
            mysql_real_escape_string($_REQUEST['email']."','".
            mysql_real_escape_string($_REQUEST['comments']."'");

         // redirect them back here
         header("Location: [URL unfurl="true"]http://www.mysite.com/feedback.php?action=done");[/URL]
         exit;
    } else {
       ?>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Feedback</title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
</head>

<body>
<h1>Our Feedback Form</h1>

   [red][b]<?php if ($_REQUEST['a'] == 'done') { ?>[/b][/red]

<p><em>Thank you for your valuable feedback!</em></p>

   [red][b]<?php } else { ?>[/b][/red]

<p>Please enter the fields below.</p>
<form action="feedback.php" method="post" name="feedback" id="feedback">
  <table cellspacing="0">
    <tr>
      <td>Your name:</td>
      <td><input name="name" type="text" id="name"></td>
    </tr>
    <tr>
      <td>E-mail address:</td>
      <td><input name="email" type="text" id="email"></td>
    </tr>
  </table>
  <p><strong>Comments about our site:</strong></p>
  <p> 
    <textarea name="comments" id="comments"></textarea>
  </p>
  <p>
    <input type="submit" name="Submit" value="Submit">
  </p>
</form>

  [red][b]<?php } else { ?>[/b][/red]

</body>
</html>

Just an example!
See how this time, if they hit Reload, there will be no resubmission of variables--All they will get is that "thank you" screen again!

_{I REALLY hope that helps.}
Will

skiflyer · Mar 19, 2004

apatterno answered your question in context. But to supply the answer to the simple question of how do I clear the $_POST array (or any of the system arrays for that matter)...

Code:

$_POST=array();

Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

How to clear $_POST values?

JediDan

Programmer

LordGarfield

IS-IT--Management

apatterno

Programmer

skiflyer

Programmer

Similar threads

Part and Inventory Search

Sponsor