Warning: Cannot Modify Headers Error

[timothyarden]

Hi Everyone am having errors with this:

Warning: Cannot modify header information - headers already sent by (output started at /------/--------/public_html/-------------------------.com/--------------------/classes/mobile.php:15) in /------/--------/public_html/-------------------------.com/--------------------/classes/mobile.php on line 6

 

Here is mobile.php

<?php // line 1
// mobile.php // line 2
class mobile_redirection { // line 3
function __construct($pagename = NULL){ // line 4
if(preg_match('/(alcatel|amoi|android|avantgo|blackberry|benq|cell|cricket|docomo|elaine|htc|iemobile|iphone|ipad|ipaq|ipod|j2me|java|midp|mini|mmp|mobi|motorola|nec-|nokia|palm|panasonic|philips|phone|playbook|sagem|sharp|sie-|silk|smartphone|sony|symbian|t-mobile|telus|up\.browser|up\.link|vodafone|wap|webos|wireless|xda|xoom|zte)/i', $_SERVER['HTTP_USER_AGENT'])) { // line 5
if(isset($pagename)){ header('Location: http://www.----------------------------.com/mobile/'.$pagename); } else { header('Location: http://www.-------------------------------.com/mobile/'); } // line 6
} else { // line 7
return false; // line 8
} // line 9
} // line 10
} // line 11

?> // line 13

 

I dont understand why there is an error on line fifteen as it doesn't exist and I dont know whats wrong on line 6.

 

When someone goes to my domain it the index file the error comes up but what should happen is if they are a mobile they are redirected to a mobile sub directory or if they aren't a mobile they should be redirected to form.php.

<?php

// Login or Sign Up

 

require('classes/mobile.php');

$mobile = new mobile_redirection('form.php');

 

if($mobile === false){

header('Location: form.php');

}

 

 

?>

 

Any ideas why this isn't happening?

 

Also, it isnt redirecting to form.php yet but if they get there and submit it will be using sessions: is it okay to use headers to redirect from 1.php to 2.php and then on 2.php start_session()?

 

Thanks for reading and for any help in advance,

Timothy

[Jessica]

Did you read the sticky on this topic? You appear to have whitespace at the beginning of the file.

[timothyarden]

No, Could you please send a link to the sticky, when I searched this site before with the error it returned nothing.

 

Thanks for the fast response

[trq]

The sticky as at the top of this very board. It's pretty hard to miss.

[timothyarden]

I read that before but it doesn't have anything about whitespace so I thought I must have read the wrong thing. Okay, thanks. Ill try without white space and see how I go.

[timothyarden]

Thanks for the help again Jessica and trq. Right again as always

[timothyarden]

Oh, 2 quick questions - is a comment counted as whitespace?

And does session need to come before header() or the opposite way round? (or doesn't it matter)