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# get_defined_constants

(PHP 4 >= 4.1.0, PHP 5)

get_defined_constants -- Returns an associative array with the names of all the constants and their values

## Description

array get_defined_constants ( [mixed categorize] )

This function returns the names and values of all the constants currently defined. This includes those created by extensions as well as those created with the define() function.

For example the line below:

`<?php print_r(get_defined_constants()); ?>`

will print a list like:

    Array
    (
        [E_ERROR] => 1
        [E_WARNING] => 2
        [E_PARSE] => 4
        [E_NOTICE] => 8
        [E_CORE_ERROR] => 16
        [E_CORE_WARNING] => 32
        [E_COMPILE_ERROR] => 64
        [E_COMPILE_WARNING] => 128
        [E_USER_ERROR] => 256
        [E_USER_WARNING] => 512
        [E_USER_NOTICE] => 1024
        [E_ALL] => 2047
        [TRUE] => 1
    )

As of PHP 5, an additional parameter, categorize, may be passed, causing this function to return a multi-dimensional array with categories in the keys of the first dimension and constants and their values in the second dimension.

`<?php define("MY_CONSTANT", 1); print_r(get_defined_constants(true)); ?>`

The above example will output something similar to:

    Array
    (
        [internal] => Array
            (
                [E_ERROR] => 1
                [E_WARNING] => 2
                [E_PARSE] => 4
                [E_NOTICE] => 8
                [E_CORE_ERROR] => 16
                [E_CORE_WARNING] => 32
                [E_COMPILE_ERROR] => 64
                [E_COMPILE_WARNING] => 128
                [E_USER_ERROR] => 256
                [E_USER_WARNING] => 512
                [E_USER_NOTICE] => 1024
                [E_ALL] => 2047
                [TRUE] => 1
            )

        [pcre] => Array
            (
                [PREG_PATTERN_ORDER] => 1
                [PREG_SET_ORDER] => 2
                [PREG_OFFSET_CAPTURE] => 256
                [PREG_SPLIT_NO_EMPTY] => 1
                [PREG_SPLIT_DELIM_CAPTURE] => 2
                [PREG_SPLIT_OFFSET_CAPTURE] => 4
                [PREG_GREP_INVERT] => 1
            )

        [user] => Array
            (
                [MY_CONSTANT] => 1
            )

    )

> Note: The value of the categorize parameter is irrelevant, only its presence is considered.

See also defined(), get_loaded_extensions(), get_defined_functions(), and get_defined_vars().

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