array_key_exists
Description
Checks if the given key or index exists in the array
Syntax
array_key_exists ( mixed $key , array $array ) : bool
Parameters
keyValue to check.
arrayAn array with keys to check.
Return
Returns TRUE on success or FALSE on failure.
Examples
1
<? $key = 1; $array = array(0, 1); $return = array_key_exists($key, $array); var_export($return); ?>
true
2
<?
$key = "b";
$array = array("a" => 0, "b" => 1);
$return = array_key_exists($key, $array);
var_export($return);
?>true
3
<? $key = 1; $array = array(0, null); $return = array_key_exists($key, $array); var_export($return); ?>
true
4
<?
$key = "b";
$array = array("a" => 0, "b" => null);
$return = array_key_exists($key, $array);
var_export($return);
?>true
