SUPERGLOBALS(3) 1 SUPERGLOBALS(3)
Superglobals - Superglobals are built-in variables that are always available in all scopes
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 $variable; to access them within functions or methods.
These superglobal variables are:
o$GLOBALS
o$_SERVER
o$_GET
o$_POST
o$_FILES
o$_COOKIE
o$_SESSION
o$_REQUEST
o$_ENV
+--------+---------------------------------------+
|Version | |
| | |
| | Description |
| | |
+--------+---------------------------------------+
| 4.1.0 | |
| | |
| | Superglobals were introduced to PHP. |
| | |
+--------+---------------------------------------+
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.
variable scope, The variables_order directive, The filter extension.
PHP Documentation Group SUPERGLOBALS(3)
