get_defined_constants

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

&reftitle.description; `array` `get_defined_constants` `bool` `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.

&reftitle.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.

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

  &example.outputs.similar;

      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
              )

      )

&reftitle.returnvalues;

Returns an array of constant name => constant value array, optionally groupped by extension name registering the constant.

&reftitle.examples;

### `get_defined_constants` Example

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

&example.outputs.similar;

    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
    )

&reftitle.seealso;

- `defined`
- `constant`
- `get_loaded_extensions`
- `get_defined_functions`
- `get_defined_vars`