Php/docs/array.constants
From Get docs
Predefined Constants
The constants below are always available as part of the PHP core.
CASE_LOWER
(int)-
CASE_LOWER
is used with array_change_key_case() and is used to convert array keys to lower case. This is also the default case for array_change_key_case(). CASE_UPPER
(int)-
CASE_UPPER
is used with array_change_key_case() and is used to convert array keys to upper case.
Sorting order flags:
SORT_ASC
(int)-
SORT_ASC
is used with array_multisort() to sort in ascending order. SORT_DESC
(int)-
SORT_DESC
is used with array_multisort() to sort in descending order.
Sorting type flags: used by various sort functions
SORT_REGULAR
(int)-
SORT_REGULAR
is used to compare items normally. SORT_NUMERIC
(int)-
SORT_NUMERIC
is used to compare items numerically. SORT_STRING
(int)-
SORT_STRING
is used to compare items as strings. SORT_LOCALE_STRING
(int)-
SORT_LOCALE_STRING
is used to compare items as strings, based on the current locale. Added in PHP 5.0.2. SORT_NATURAL
(int)-
SORT_NATURAL
is used to compare items as strings using "natural ordering" like natsort(). Added in PHP 5.4.0. SORT_FLAG_CASE
(int)-
SORT_FLAG_CASE
can be combined (bitwise OR) withSORT_STRING
orSORT_NATURAL
to sort strings case-insensitively. Added in PHP 5.4.0.
Filter flags:
ARRAY_FILTER_USE_KEY
(int)-
ARRAY_FILTER_USE_KEY
is used with array_filter() to pass each key as the first argument to the given callback function. Added in PHP 5.6.0. ARRAY_FILTER_USE_BOTH
(int)-
ARRAY_FILTER_USE_BOTH
is used with array_filter() to pass both value and key to the given callback function. Added in PHP 5.6.0.
COUNT_NORMAL
(int)COUNT_RECURSIVE
(int)EXTR_OVERWRITE
(int)EXTR_SKIP
(int)EXTR_PREFIX_SAME
(int)EXTR_PREFIX_ALL
(int)EXTR_PREFIX_INVALID
(int)EXTR_PREFIX_IF_EXISTS
(int)EXTR_IF_EXISTS
(int)EXTR_REFS
(int)