[SOLVED] Trouble when declaring "session_start()"???!!!

[GuyFreakz]

Hi guys, I'm a student who learns php. And now I'm learning about session.

I face a problem when i started session with session_start().

First, i declared the "session_start" in page1.php like this

 

<?php

  session_start();

  $_SESSION["username"]="Kay";

?>

 

And after that i running my opera browser and there is no problem when i entered http://localhost/practice/page1.php.

But then i make another page2.php

 

<?php

  session_start();

  $user = $_SESSION["username"];

  echo $user;

?>

 

and got these messages:

-------------------------------------------------------------------------

Warning: session_start() [function.session-start]: Cannot send session cookie - headers already sent by (output started at C:\xampp\htdocs\practice\page2.php:1) in C:\xampp\htdocs\practice\page2.php on line 2

 

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at C:\xampp\htdocs\practice\page2.php:1) in C:\xampp\htdocs\practice\page2.php on line 2

 

Kay

-------------------------------------------------------------------------

 

I've tried to close the browser but still the messages appeared. Then i copy the page2.php to another folder, and when i opened again there is no problem. My question is where is my fault?

 

Thank you 

[.josh]

The error tells you the problem.  You cannot have output before starting a session.  Make sure there is no output, not even blank lines or whitespace. 

[corbin]

http://www.phpfreaks.com/forums/index.php/topic,37442.0.html

[premiso]

Make sure you do not have an enter before the <?php

 

IE:

WRONG

<?php
//code here
?>

 

RIGHT

<?php
// code here
?>

[GuyFreakz]

Make sure you do not have an enter before the <?php

 

IE:

WRONG

<?php
//code here
?>

 

RIGHT

<?php
// code here
?>

 

I've checked it many times and there is not even 1 space or tab. I'm not sure but after i followed the link given by corbin, they tell me that the trouble may lays on the text editor. I usually used Notepad++, but i've created the page1.php using TextPad and just for fun i made the second used notepad++. After that i copy the content of page2.php to new document i created in textpad and save it there but in different document.

So my deduction is there is error in Notepad++, when it create a new document, just maybe, it's automatically add an invisible character at the beginning of document.

[radalin]

It's possible that \r (new line for most ms editors) or \n (newline for rest of the world:) might be added with some editors. These are invisible characters, these characters are recognised by the editor and shown.

 

When you open a .txt file with vi you see strange chars like ^M, this one refers to "\r". This might be the problem. I had encountered this problem too. Use an editor which you trust

[BioBob]

If its the text editor you are using, skip newline or \r or \n and just put it all on one line...

 

<?php session_start();

 

Then plug in your code from there.  You can also try OUTPUT BUFFERING (OB) but it may cause a performance hit. 

 

<?
ob_start();
session_start();

ob_end_flush();

$user = $_SESSION['user'];
echo $user;

[GuyFreakz]

It's possible that \r (new line for most ms editors) or \n (newline for rest of the world:) might be added with some editors. These are invisible characters, these characters are recognised by the editor and shown.

 

When you open a .txt file with vi you see strange chars like ^M, this one refers to "\r". This might be the problem. I had encountered this problem too. Use an editor which you trust

 

Ho... so it can be like that huh?! I see that's explained why my code always generates error. Thx guyz .

[PFMaBiSmAd]

When the error refers to output occurring on line 1 and you have checked and removed any possible content before the <?php tag, then the error is most likely due to the page being saved in UTF-8 encoding and the BOM (Byte Order Mark) characters that your editor places at the start of the file is the problem. Either save your file as ANSI/ASCII or if you must save it as UTF-8,  pick the option in your editor to save it without the BOM (or get a different editor.)

[GuyFreakz]

When the error refers to output occurring on line 1 and you have checked and removed any possible content before the <?php tag, then the error is most likely due to the page being saved in UTF-8 encoding and the BOM (Byte Order Mark) characters that your editor places at the start of the file is the problem. Either save your file as ANSI/ASCII or if you must save it as UTF-8,  pick the option in your editor to save it without the BOM (or get a different editor.)

 

You're right!!! That's the best solution. After i changed the setting of my notepad++, there is no error anymore. Thank you very much. Thank you!!!  :D :D