PHP

PHP Information

Show installed PHP version

php -v

List active compiled php modules

php -m

Show php configuration and environment information

php -i

Run Script

Manually execute a PHP script

php -q <script>

PHP Interactive Shell

Start interactive shell from the command line

php -a

Exit interactive shell

quit
CTRL+C

Simple PHP Server

Start a server in the current directory

php -S localhost:8000

Output Strings

Output readable/detailed debugging information about a variable

print_r($var)
var_dump($var)

Outputs parsable string representation of variable

var_export($var)

Output string

echo $var;
print($var);

Output formatted string

printf($format, $value)

Superglobals

Context, configuration and environment variables available in all scopes

• $GLOBALS: All variables available in global scope

• $_ENV: Environment variables

• $_SERVER: Server and execution environment information

• $_SESSION: Session variables available to the current script

• $_COOKIES: Cookie variables available to the current script via HTTP Cookies

• $_FILES: Items uploaded to the current script via the HTTP POST method

• $_GET: Variables passed to the current script via URL GET parameters

• $_POST: Variables passed to the current script via the HTTP POST method

• $_REQUEST: All variables from $_GET, $_POST and $_COOKIE

Note: Order and availability of $_ENV (E), $_GET (G), $_POST (P), $_COOKIES (C), $_SERVER (S) is set by variables_order setting in php.ini (Default: variables_order = "EGPCS")

Environment Values

Directly query OS environment variables

getenv();
getenv($name);

Extensions

Check if extension is loaded (eg. 'gd' image library)

extension_loaded(<extension-name>);
extension_loaded('gd');

Introspection

Class Introspection

Get declared classes, traits and interfaces

get_declared_classes()
get_declared_traits()
get_declared_interfaces()

Get defined vars, constants and functions

get_defined_vars()
get_defined_constants()
get_defined_functions()

Check if a class exists

class_exists($class_name)

Get the parent classes, interfaces and traits a class uses

class_parents($class_name_or_instance)
class_implements($class_name_or_instance)
class_uses($class_name_or_instance)

Get parent class, methods or vars from a class

get_parent_class($class_name_or_instance)
get_class_methods($class_name_or_instance)
get_class_vars($class_name)

Object Introspection

Test for an object and get the class an object belongs to

is_object($object)
get_class($object)

Check if a method or property exists on an object

method_exists($object, $method_name)
property_exists($object, $property_name)

Get object vars and object parent class

get_object_vars($object)
get_parent_class($object)

Get the type of a variable

gettype($var)

Test if an object is a particular class

is_a($object, $class_name)
$object instanceof $class

Array Introspection

Output array keys

array_keys($array)

Typecast object to array and output list of keys

print_r(array_keys((array)$object))