PHP: Initialize session data

Description

bool session_start ( void )

session_start() creates a session or resumes the current one based on the current session id that's being passed via a request, such as GET, POST, or a cookie.

If you want to use a named session, you must call session_name() before calling session_start().

session_start() will register internal output handler for URL rewriting when trans-sid is enabled. If a user uses ob_gzhandler or like with ob_start(), the order of output handler is important for proper output. For example, user must register ob_gzhandler before session start.

Return Values

This function always returns TRUE.

ChangeLog

Version Description

4.3.3 As of now, calling session_start() while the session has already been started will result in an error of level E_NOTICE. Also, the second session start will simply be ignored.

Examples

Example #1 A session example: page1.php


<?php

// page1.php



session_start();



echo 'Welcome to page #1';



$_SESSION['favcolor'] = 'green';

$_SESSION['animal']   = 'cat';

$_SESSION['time']     = time();



// Works if session cookie was accepted

echo '<br /><a href="page2.php">page 2</a>';



// Or maybe pass along the session id, if needed

echo '<br /><a href="page2.php?' . SID . '">page 2</a>';

?>

After viewing page1.php, the second page page2.php will magically contain the session data. Read the session reference for information on propagating session ids as it, for example, explains what the constant SID is all about.

Example #2 A session example: page2.php


<?php

// page2.php



session_start();



echo 'Welcome to page #2<br />';



echo $_SESSION['favcolor']; // green

echo $_SESSION['animal'];   // cat

echo date('Y m d H:i:s', $_SESSION['time']);



// You may want to use SID here, like we did in page1.php

echo '<br /><a href="page1.php">page 1</a>';

?>

Notes

Note: If you are using cookie-based sessions, you must call session_start() before anything is outputted to the browser.

Note: Use of zlib.output_compression is recommended rather than ob_gzhandler()

session_start

Description

Return Values

ChangeLog

Examples

Notes

See Also