PHP Options/Info Functions
PHP Manual

extension_loaded

Find out whether an extension is loaded

Description

bool extension_loaded(string $extension)

Finds out whether the extension is loaded.

Parameters

extension

The extension name. This parameter is case-insensitive.

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 extension is loaded, false otherwise.

Examples

Example #1 extension_loaded example

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

See Also

  • get_loaded_extensions
  • get_extension_funcs
  • phpinfo
  • dl
  • function_exists