PHP Options/Info Functions
PHP Manual

extension_loaded

Find out whether an extension is loaded

Description

bool extension_loaded ( string $name )

Finds out whether the extension is loaded.

Parameters

name

The extension name.

You can see the names of various extensions by using phpinfo or if you're using the CGI or CLI version of PHP you can use the -m switch to list all available extensions: 

$ php -m
[PHP Modules]
xml
tokenizer
standard
sockets
session
posix
pcre
overload
mysql
mbstring
ctype

[Zend Modules]

Return Values

Returns TRUE if the extension identified by name is loaded, FALSE otherwise.

Examples

Example #1 extension_loaded example

<?php
if (!extension_loaded('gd')) {
    if (!dl('gd.so')) {
        exit;
    }
}
?>

Changelog

Version Description
5.0.0 extension_loaded uses the internal extension name to test whether a certain extension is available or not. Most internal extension names are written in lower case but there may be extensions available which also use uppercase letters. Prior to PHP 5, this function compared the names case sensitively.

See Also

  • get_loaded_extensions
  • get_extension_funcs
  • phpinfo
  • dl
  • function_exists