array_key_exists is not working for large multidimensional array. For ex
$arr = array(
'1' => 10,
'2' => array(
'21' => 21,
'22' => 22,
'23' => array(
'test' => 100,
'231' => 231
),
),
'3' => 30,
'4' => 40
);
array_key_exists('test',$arr) returns 'false' but it works with some simple arrays.
array_key_exists does NOT work recursive (as Matti Virkkunen already pointed out). Have a look at the PHP manual, there is the following piece of code you can use to perform a recursive search:
<?php
function array_key_exists_r($needle, $haystack)
{
$result = array_key_exists($needle, $haystack);
if ($result) return $result;
foreach ($haystack as $v) {
if (is_array($v)) {
$result = array_key_exists_r($needle, $v);
}
if ($result) return $result;
}
return $result;
}
array_key_exists doesn't work on multidimensionaml arrays. if you want to do so, you have to write your own function like this:
function array_key_exists_multi($n, $arr) {
foreach ($arr as $key=>$val) {
if ($n===$key) {
return $key;
}
if (is_array($val)) {
if(multi_array_key_exists($n, $val)) {
return $key . ":" . array_key_exists_multi($n, $val);
}
}
}
return false;
}
this returns false if the key isn't found or a string containing the "location" of the key in that array (like 2:23:test) if it's found.
$test_found = false;
array_walk_recursive($arr,
function($v, $k) use (&$test_found)
{
$test_found |= ($k == 'test');
});
This requires PHP 5.3 or later.
Here is another one, works on any dimension array
function findValByKey($arr , $keySearch){
$out = null;
if (is_array($arr)){
if (array_key_exists($keySearch, $arr)){
$out = $arr[$keySearch];
}else{
foreach ($arr as $key => $value){
if ($out = self::findValByKey($value, $keySearch)){
break;
}
}
}
}
return $out;
}
