PHP
downloads | documentation | faq | getting help | mailing lists | reporting bugs | php.net sites | links | conferences | my php.net

search for in the

$GLOBALS> <Predefined variables
Last updated: Fri, 10 Oct 2008

view this page in

Superglobals

SuperglobalsSuperglobals are built-in variables that are always available in all scopes

Description

Several predefined variables in PHP are "superglobals", which means they are available in all scopes throughout a script. There is no need to do global $variable; to access them within functions or methods.

These superglobal variables are:

ChangeLog

Version Description
4.1.0 Superglobals were introduced to PHP.

Notes

Note: Variable availability
By default, all of the superglobals are available but there are directives that affect this availability. For further information, refer to the documentation for variables_order.

Note: Dealing with register_globals
If the deprecated register_globals directive is set to on then the variables within will also be made available in the global scope of the script. For example, $_POST['foo'] would also exist as $foo.
For related information, see the FAQ titled "How does register_globals affect me?"

Note: Variable variables
Superglobals cannot be used as variable variables inside functions or class methods.



add a note add a note User Contributed Notes
Superglobals
Tibor > rocketmachine.com
06-Oct-2008 07:00
You can use superglobals to make your variables available everywhere without declaring them global.

<?php

$_ENV
['mystring'] = 'Hello World';
$_ENV['myarray'] = array('Alpha', 'Bravo', 'Charlie');

function
test() {
    print
$_ENV['mystring'];
   
print_r($_ENV['myarray']);
}

test();

?>

$GLOBALS> <Predefined variables
Last updated: Fri, 10 Oct 2008
 
 
show source | credits | sitemap | contact | advertising | mirror sites