[PHP] Search value in multidimensional array

get_by_key_value.php

<?php

/**
 * Search value through multi dimensional array by column key and return first found sub array or corresponding key.
 * This method preserves the original array keys.
 * 
 * Multiple returns :
 * - The sub-array if value is found
 * - A mixed value corresponding to the key (if $onlyKey is set to true)
 * - false if an error occured or value is not found
 * 
 * A warning is triggered if :
 * - Searched key does not exist in array
 * - Searched key is not present in all sub-array
 * 
 * @param mixed  $columnKey  The searched column name in array (type sensitive)
 * @param mixed  $needle     The searched value
 * @param array  $array      The array
 * @param bool   $onlyKey    If true the function will returns only the corresponding key
 * @param bool   $strict     If true the function will search for identical elements in the haystack
 * 
 * @return false|mixed|array
 */
function get_by_key_value($columnKey, $needle, array $haystack, bool $onlyKey = false, bool $strict = false)
{
    // The value can't be found in empty array
    if(empty($haystack)) {
        return false;
    }
    
    // Retrieve only the values of $columnKey from $array
    $columns = array_column($haystack, $columnKey);
    if(empty($columns)) {
        trigger_error("get_by_key_value() : The column key {$columnKey} does not exist in the array", E_USER_WARNING);
        return false;
    }
    
    // Set the real keys of $array
    $keys = array_keys($haystack);
    if(count($keys) !== count($columns)) {
        trigger_error("get_by_key_value() : The keys in haystack must be the same", E_USER_WARNING);
        return false;
    }
    $correctKeys = array_combine($keys, $columns);
    
    // Searches in correct keys for the given value and returns the first corresponding key if successful
    $found = array_search($needle, $correctKeys, $strict);
    
    // Returns the key
    if($onlyKey) {
        return $found;
    }
    
    // Returns the data or false if not found
    if($found === false) {
        return false;
    }
    return $haystack[$found];
}


/**
 * This methods is similar to get_by_key_value but returns an array of all found sub arrays or corresponding keys.
 * This method preserves the original array keys.
 * 
 * Multiple returns :
 * - An array of sub-arrays if value are found
 * - An array of mixed values corresponding to the keys (if $onlyKey is set to true)
 * - An empty array if an error occured or value is not found
 * 
 * A warning is triggered if :
 * - Searched key does not exist in array
 * - Searched key is not present in all sub-array
 * 
 * @param mixed  $columnKey     The searched column name in array (type sensitive)
 * @param mixed  $needle        The searched value
 * @param array  $array         The array
 * @param bool   $onlyKey       If true the function will returns only the corresponding key
 * @param bool   $strict        If true the function will search for identical elements in the haystack
 * @param bool   $baseHaystack  *Only for recursion, do not use*
 * @param bool   $keys          *Only for recursion, do not use*
 * 
 * @return array
 */
function get_by_key_value_multiple($columnKey, $needle, array $haystack, bool $onlyKey = false, bool $strict = false, array $baseHaystack = [], array $keys = [])
{
    if(empty($baseHaystack)) {
        $baseHaystack = $haystack;
    }
    $copy = $haystack;
    $found = get_by_key_value($columnKey, $needle, $copy, true, $strict);
    if($found === false) {
        if($onlyKey) {
            return $keys;
        }
        $result = [];
        foreach($keys as $key) {
            $result[$key] = $baseHaystack[$key];
        }
        return $result;
    }
    $keys[] = $found;
    unset($copy[$found]);
    return get_by_key_value_multiple($columnKey, $needle, $copy, $onlyKey, $strict, $baseHaystack, $keys);
}


// Tests
$haystack = [
    'a' => [
        'keyA' => 'Value A',
        10 => 42,
        14 => 'Value C',
        'keyB' => 'Value B',
    ],
    12 => [
        'keyA' => 'Value A12',
        10 => '54',
        15 => 'Value D',
        'keyB' => 'Value B',
    ],
];

var_dump(get_by_key_value('keyA', 'Value A12', $haystack)); // === $haystack[12]
var_dump(get_by_key_value(10, 42, $haystack)); // === $haystack['a']
var_dump(get_by_key_value(10, '42', $haystack, true)); // === 'a'
var_dump(get_by_key_value('10', '42', $haystack, false, true)); // === false (strict mode)
var_dump(get_by_key_value(15, 'Value D', $haystack)); // === false + Warning : 15 does not exists in $haystack[12]

// Multiple values attempted
var_dump(get_by_key_value('keyB', 'Value B', $haystack)); // === $haystack['a'] because is the first occurence
var_dump(get_by_key_value_multiple('keyB', 'Value B', $haystack)); // === array[$haystack['a'], $haystack[12]]
var_dump(get_by_key_value_multiple('keyB', 'Value C', $haystack)); // === empty array