ARRAY_KEYS
Return all the keys or a subset of the keys of an array
SYNTAX
array_keys ( array $array ) : array
array_keys ( array $array , mixed $search_value [, bool $strict = FALSE ] ) : array
PARAMETERS
array
An array containing keys to return.
search_value
If specified, then only keys containing these values are returned.
strict
Determines if strict comparison (===) should be used during the search.
RETURN
Returns an array of all the keys in array.
EXAMPLES
ARRAY | INDEXED
Array
(
[0] => 0
[1] => 1
[2] => 2
[3] => 3
[4] => 4
)
ARRAY | ASSOCIATIVE
Array
(
[0] => a
[1] => b
[2] => c
[3] => d
[4] => e
)
SEARCH_VALUE | INDEXED
Array
(
[0] => 2
[1] => 4
)
SEARCH_VALUE | ASSOCIATIVE
Array
(
[0] => c
[1] => e
)
STRICT | INDEXED
Array
(
[0] => 4
)
STRICT | ASSOCIATIVE
Array
(
[0] => e
)