Php/docs/function.get-defined-constants
get_defined_constants
(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
Description
get_defined_constants
([ bool $categorize
= FALSE
] ) : array
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.
Parameters
categorize
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.
<?phpdefine("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 ) )
Return Values
Returns an array of constant name => constant value array, optionally groupped by extension name registering the constant.
Examples
Example #1 get_defined_constants() Example
<?phpprint_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 )
See Also
- defined() - Checks whether a given named constant exists
- get_loaded_extensions() - Returns an array with the names of all modules compiled and loaded
- get_defined_functions() - Returns an array of all defined functions
- get_defined_vars() - Returns an array of all defined variables