Why isn't this code looping?

darthjones

<?php

if(isset($_POST['logout']))
{
  setcookie("logincookie", FALSE);
  header("Location: " . $_SERVER['PHP_SELF']);
  exit;
}

if(isset($_POST['login']))
{
  setcookie("logincookie", $_POST['loginName'], time()+3600); // expire in 1 hour
  header("Location: " . $_SERVER['PHP_SELF']);
  exit;
}

if(isset($_COOKIE['logincookie']))
{
  echo "You are logged in as " . $_COOKIE['logincookie'] . ".";

  ?>

  <hr>
  <form action=<? echo $_SERVER['PHP_SELF']; ?> method=post>
  <input type=hidden name=logout>
  <input type=submit name=submit value="Log out">
  </form>

  <?

}
else
{
  echo "You are not logged in, please enter your name:";

  ?>

  <form action=<? echo $_SERVER['PHP_SELF']; ?> method=post>
  <input type=text name=loginName>
  <input type=hidden name=login>
  <input type=submit name=submit value="Log in">
  </form>

  <?

}

?>

This code actually works the way I want it to. However, there are a few things about it that I think shouldn't work. I need your help to understand what's going on here.

After the user inputs his/her name into the text box and the submit button ("Log in") is pressed, shouldn't there be an infinite loop because of the second if statement? Doesn't header("Location: " . $_SERVER['PHP_SELF']); cause the whole page to reload without changing the status of the 'login' variable? If that's the case, then this if statement should run every single time the page is reloaded.
Why is it that if you click on the submit button ("Log in") button without writing something in the text box (look in the last else statement), the second if statement does not run? Shouldn't <input type=hidden name=login> create or set a "login" variable independent of whether the "loginName" text box was filled?

Any help would be appreciated.

Thanks

devinemke

darthjones wrote:
After the user inputs his/her name into the text box and the submit button ("Log in") is pressed, shouldn't there be an infinite loop because of the second if statement? Doesn't header("Location: " . $SERVER['PHP_SELF']); cause the whole page to reload without changing the status of the 'login' variable? If that's the case, then this if statement should run every single time the page is reloaded.

there is no infinite loop because once the page is reloaded via header() the if() conditions are no longer true. the $POST['login'] var is no longer set. btw: your code could be shortened a bit. consider this:

<?php
if (isset($_POST['submit']))
{
	if ($_POST['submit'] == 'login') {setcookie('logincookie', $_POST['loginName'], time() + 3600);}
	if ($_POST['submit'] == 'logout') {setcookie('logincookie', FALSE);}
	header('location: ' . $_SERVER['PHP_SELF']);
	exit();
}

if (isset($_COOKIE['logincookie']))
{
	echo 'You are logged in as ' . $_COOKIE['logincookie'];
	$input = '';
	$submit_value = 'logout';
}
else
{
	echo 'You are not logged in, please enter your name:';
	$input = '<input type="text" name="loginName">';
	$submit_value = 'login';
}

echo '
<form action="' . $_SERVER['PHP_SELF'] . '" method="post">
' . $input . '
<input type="submit" name="submit" value="' . $submit_value . '">
</form>
';
?>

darthjones

Thanks for the info. Just to make things clear (for myself and others), using $SERVER['PHP_SELF'] will not clear the variables in $POST while using header("Location: " . $_SERVER['PHP_SELF']); will, right?

BTW, thanks for the shortened code. I'll take a closer look at it after I post this message.

devinemke

darthjones wrote:
...using $SERVER['PHP_SELF'] will not clear the variables in $POST while using header("Location: " . $SERVER['PHP_SELF']); will, right?

using [man]header[/man] redirect does not resubmit the form, so no $POST vars will be set.

darthjones

Alright. That makes a lot more sense. Thanks again. I think I'll be able to sleep more soundly tonite thanks to this.