<?php
 if(isset($_COOKIE['webSurvey']))
    
 {
 print("Your last submision time was ");
 
 die("<br />Please wait for 24 Hours before retry!");
 }
 else
 {
 extract( $_POST );
 setcookie( "webSurvey", $name, time() + 60*1);
 setcookie("time", time(), time() + 60 * 1);
}
?>

<?php
  /*** I found I must have the setcookie first or I would get errors like
       'Warning: Cannot modify header information - headers already sent by...'
  
       So where is that 'header end' cut-off line ???
  ***/
  $ptime = time();
  $waitime = 24 * 60 * 60;
  $expiretime = $waitime + time();
  
  if(!isset($_COOKIE['webSurvey'])) /* don't want to reset the waiting period */
  {  
    setcookie("webSurvey", time(), $expiretime);
    echo "setting cookie <br /><br />";  
  }  
  echo $ptime . " - was the output of time(). <br /><br />";
  echo $expiretime . " - is the value held in \$expiretime. <br /><br />";
  
  /*** Then proceed with this kind of stuff
  ***/
  if(isset($_COOKIE['webSurvey']))
  { 
    $lastime = $_COOKIE['webSurvey'];
    echo $lastime . " - was your last submision time. <br />";
    $remainingtime = $lastime + $waitime - $ptime;
    echo " - - - - - - <br />
         Please wait another $remainingtime seconds <br />
         (or " . $remainingtime / 60 / 60 . " hours) <br />";
  }
  else         /* no cookie found so 24 hr 'expiretime' has passed */
    echo "Proceed with your submission... <br /><br />";
 
  echo "<br /> - - - The End - - - <br />";  
?>

<?php
/*
 * This does not keep someone from clearing
 * their cookies and resubmitting the form
 */
if (isset($_COOKIE['webSurvey']))
{
    if (isset($_COOKIE['time']))
    {
        // Converts timestamp to formatted date
        printf('Your last submision time was %s.<br />'
              , date('Y-m-d H:i:s', $_COOKIE['time']));
    }
    echo 'Please wait for 24 hours before retry!';
}
else if (isset($_POST['btnSubmit'])) // The form was submitted
{
    // Creates $name and $btnSubmit
    // Vulnerable to injection attacks; Consider using $_POST['name'] instead
    extract($_POST);
    
    // The webSurvey cookie is not set if $name is an empty string
    if (empty($name))
        $name = 'anonymous';
    
    // More efficient than calling time() three times
    $time = time();
    
    // Cookies will expire in 24 hours (60 * 60 * 24 = 86400)
    setcookie('webSurvey', $name, $time + 86400);
    setcookie('time', $time, $time + 86400);
    
    printf('<p>Thank you, %s.</p>', $name);
}
else // No cookie, no form submitted
{
?>
    <form method="post" action="">
        Name: <input type="text" name="name" value="" />
        <input type="submit" name="btnSubmit" value="Submit" />
    </form>
<?php
}
?>

<pre style="font-size: smaller">
For Debugging:
$_POST =&gt; <?php print_r($_POST); ?>
$_COOKIE =&gt; <?php print_r($_COOKIE); ?>
</pre>

<?php
header('Content-type: text/css');
echo 'body { background-color: black; }';
?>

<?php
/*
 * This is wrong!
 */
echo 'Output before setting cookie.';
setcookie('index', 'value', time() + 86400);
?>

<?php
/*
 * This is correct
 */
setcookie('index', 'value', time() + 86400);
echo 'Output after setting cookie.';
?>

<?php
/*
 * This is also correct
 * Even though echo comes first in the code,
 * it will not be executed before setcookie()
 */
$a = true;
if ($a)
    echo 'Output without setting cookie.';
else
    setcookie('index', 'value', time() + 86400);
?>