(PHP 4 >= 4.1.0, PHP 5, PHP 7)
get_defined_constants — Returns an associative array with the names of all the constants and their values
$categorize = FALSE
] )Returns the names and values of all the constants currently defined. This includes those created by extensions as well as those created with the define() function.
categorizeCausing this function to return a multi-dimensional array with categories in the keys of the first dimension and constants and their values in the second dimension.
<?php
define("MY_CONSTANT", 1);
print_r(get_defined_constants(true));
?>
The above example will output something similar to:
Array
(
[Core] => Array
(
[E_ERROR] => 1
[E_WARNING] => 2
[E_PARSE] => 4
[E_NOTICE] => 8
[E_CORE_ERROR] => 16
[E_CORE_WARNING] => 32
[E_COMPILE_ERROR] => 64
[E_COMPILE_WARNING] => 128
[E_USER_ERROR] => 256
[E_USER_WARNING] => 512
[E_USER_NOTICE] => 1024
[E_ALL] => 2047
[TRUE] => 1
)
[pcre] => Array
(
[PREG_PATTERN_ORDER] => 1
[PREG_SET_ORDER] => 2
[PREG_OFFSET_CAPTURE] => 256
[PREG_SPLIT_NO_EMPTY] => 1
[PREG_SPLIT_DELIM_CAPTURE] => 2
[PREG_SPLIT_OFFSET_CAPTURE] => 4
[PREG_GREP_INVERT] => 1
)
[user] => Array
(
[MY_CONSTANT] => 1
)
)
Returns an array of constant name => constant value array, optionally groupped by extension name registering the constant.
| Version | Description |
|---|---|
| 5.3.1 | Windows only: Core constants are categorized under Core, previously mhash. |
| 5.3.0 | Core constants are categorized under Core, previously internal. On Windows, the Core Constants are categorized under mhash. |
| 5.2.11 |
The categorize parameter now operates appropriately.
Previously, the categorize parameter was interpreted
as !is_null($categorize), making any value other than NULL
force the constants to be categorized.
|
Example #1 get_defined_constants() Example
<?php
print_r(get_defined_constants());
?>
The above example will output something similar to:
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
)