So, I have multidimensional array (for example):
array[1][22]['name']
array[1][33]['name']
array[2][44]['name']
array[3][55]['name']
I know last array key(it's ID) (for example - [44]), how can I find value of [name] for known key?
In my guess I need something like array_search, but for key and in multidimensional array...
Here's a simple way with PHP >= 5.5.0. This assumes there is only one key 44 in the array:
echo array_column($array, 44)[0]['name'];
// or
echo current(array_column($array, 44))['name'];
Earlier versions:
foreach($array as $k => $v) { if(isset($v[44])) echo $v[44]['name']; }
You are better off changing your array structure:
$array = [
22 => [ 'name' => 'A'],
33 => [ 'name' => 'B'],
44 => [ 'name' => 'C'],
55 => [ 'name' => 'D'],
];
and simply write
$array[44]['name']
Wouldn't it be better to optimize your array for this search, for instance build another one with IDs as keys and references to the data as values?
When building your array you could:
$IDsIndex = array();
foreach(...) {
$IDsIndex[$ID] = &$data;
}
and then:
$IDsIndex[44]['name'];
I have a function that seems to work for me. Let me know if you find it lacking. Note: It has not been tested for performance on massive arrays or objects.
function arrayKeySearch(array $haystack, string $search_key, &$output_value, int $occurence = 1){
$result = false;
$search_occurences = 0;
$output_value = null;
if($occurence < 1){ $occurence = 1; }
foreach($haystack as $key => $value){
if($key == $search_key){
$search_occurences++;
if($search_occurences == $occurence){
$result = true;
$output_value = $value;
break;
}
}else if(is_array($value) || is_object($value)){
if(is_object($value)){
$value = (array)$value;
}
$result = arrayKeySearch($value, $search_key, $output_value, $occurence);
if($result){
break;
}
}
}
return $result;
}
