PHP redirection using 'header' not working

cab

Hi,

I can't seem to get PHP to redirect the browser using the "header" command.

The code executes up to the point of the "header" statement but code execution stops and the browser is not redirected?

Any help appreciated.

Code follows ....

<?php
//echo"<body bgcolor=\"#FDFDCE\" background=\"images/marble.jpg\">";

// connect to database
include_once('connection.php');

$link = mysql_connect(HOST,USER,PASSWORD)
or die ('Cannot Connect to database');
mysql_select_db(DATABASE,$link);

// does username and password match?
$qry = "SELECT username,password FROM users WHERE username= '$user' AND password= '$pwd'";

$result = mysql_query($qry,$link);
$rows = mysql_num_rows($result);

if (!$rows)
// query failed - incorrect password
{
//echo"INCORRECT PASSWORD";
Header ("Location: IncorrectPassword.php");
exit;
}
else
// query successful - correct password
// register session variables to confirm that user is logged on
//echo"CORRECT PASSWORD";
session_start();
$LoggedOn="YES";
$UserLoggedOn=$user;
$PasswordLoggedOn=$pwd;
session_register("UserLoggedOn");
session_register("PasswordLoggedOn");
{
Header ("Location: CorrectPassword.php?UserName=$user");
exit;
}

// close the database connection
mysql_close();

rehfeld

put this at the top of your code

ini_set('display_errors', 1);
error_reporting(E_ALL);

cab

Thanks for this I now have more clues ...

The script now returns the following error:

Warning: Cannot modify header information - headers already sent by (output started at /homepages/39/d92194205/htdocs/CheckUserPassword.php:2) in /homepages/39/d92194205/htdocs/CheckUserPassword.php on line 26

But what does this mean?

Is there any other way to redirect the browser?

Thanks

rehfeld

headers MUST be sent before ANY other output is sent to the browser

that means no echo or print, or even spaces or blank lines can be output.

bad

<?php

echo '     '; // <--- thats output
header(...);

?>

bad

<html> <---- thats output
<?php

header(...);

?>

good

<?php

header(...);

?>

also, works

<?php
ob_start(); // start output buffering

echo '     '; 
header(...);

?>

Weedpacket

Originally posted by cab
Thanks for this I now have more clues ...

The script now returns the following error:

Warning: Cannot modify header information - headers already sent by (output started at /homepages/39/d92194205/htdocs/CheckUserPassword.php:2) in /homepages/39/d92194205/htdocs/CheckUserPassword.php on line 26

But what does this mean?

Top thread in the forum is this. Have a look at item 2. That should give you an idea what's going on.

pwicks

"Header already sent" basically means that the Web server has sent HTML to the browser already.

It's something you can't do twice. You're no longer connected to the Web server, and all rendering is done.

This is the HTTP equivalent of missing the boat.

You can get around the problem you're having, by buffering all output and getting it all out at once.

Put the following line at the top of your script, before any echos, prints, or raw HTML, (including any "blank" lines outside of your php tags!):

ob_start();

...and this line at the end, after all echos, prints, et al.

ob_end_flush();

So, you're putting these lines just after and before your php tags, repsectively:

<?php
on_start();

//all your code here

ob_end_flush();
?>

If this doesn't apprear to work, there's some HTML or a blank line outside of your php tags. Delete them and it will work.

There's one variation on this, which is to use ob_end_clean(), which does the same thing as ob_end_flush() but also deletes everything in the buffer (if your "data" is already on-screen, do you need it in memory? You may or may not.)

The only thing you could do to prevent this from working is to try to use both a POST and a session at the same time...that sort of thing.

I think this will eliminate the problem.

rehfeld

ps, you dont need ob_end_flush()

php automatically flushes the output buffer at the end of the script execution.

Weedpacket

Originally posted by pwicks
"Header already sent" basically means that the Web server has sent HTML to the browser already. .....

Thanks for the duplication.