PHP Function search_multidimensional_array() to Search Multidimensional Array

search_multidimensional_array() works with unlimited multidimensional arrays both associative arrays and indexed arrays and the function can be set to ignore case if desired.

array_search() is a great php function for finding if a value is an array but it only works with a one dimensional array.

The custom function below search_multidimensional_array() works with unlimited multidimensional arrays both associative arrays and indexed arrays and the function can be set to ignore case if desired.

function search_multidimensional_array($needle, $haystack, $caseIgnore = false) { foreach ($haystack as $key => $value) { if (is_array($value)) { // recursively search in sub-arrays $result = search_multidimensional_array($needle, $value, $caseIgnore); if ($result !== false) { // merge the current key with the deeper result, to maintain the full path return [$key => $result]; } } // case-insensitive comparison if $caseIgnore is true elseif (($caseIgnore && strcasecmp($value, $needle) === 0) || (!$caseIgnore && $value === $needle)) { // return the key where the value is found return $key; } } return false; // if not found }

As an example lets assume the following multidimensional array ...

$marks = array(
    
    "Ankit" => array(
        
        "C" => array(

             "xx" => 178,
             "ss" => 198,
             "aa" => array(
                  "necro" => "helper",
                  "monkey" => "oo oo",
                  "dog" => "pitbull"
               ),
             ),
             
        "DCO" => 85,
        "FOL" => 74,
    ),
        
    "Ram" => array(

        "C" => 78,
        "DCO" => 98,
        "FOL" => 46,
    ),

    "Anoop" => array(

        "C" => 88,
        "DCO" => 46,
        "FOL" => 99,
    ),
);

search_multidimensional_array("helper", $marks); ...

returns Array ( [Ankit] => Array ( [C] => Array ( [aa] => necro ) ) )

An example of using the function search_multidimensional_array() with an indexed array ...

$students = array(
    array("Alice", 22, "steve"),
    array("Bob", 20, array("Science", array("A+", "F"))),
    array("Charlie", 23, array("Literature", "History")),
);

search_multidimensional_array("A+", $students); ...

returns Array ( [1] => Array ( [2] => Array ( [1] => 0 ) ) )