Switch two items in associative array

Question

Example:

$arr = array(
  \'apple\'      => \'sweet\',
  \'grapefruit\' => \'bitter\',
  \'pear\'       => \'tasty\',
  \'banana\'     => \'yellow\'
)         


        

Answer 1

I'll share my short version too, it works with both numeric and associative arrays.

array array_swap ( array $array , mixed $key1 , mixed $key2 [, bool $preserve_keys = FALSE [, bool $strict = FALSE ]] )

Returns a new array with the two elements swapped. It preserve original keys if specified. Return FALSE if keys are not found.

function array_swap(array $array, $key1, $key2, $preserve_keys = false, $strict = false) {
    $keys = array_keys($array);
    if(!array_key_exists($key1, $array) || !array_key_exists($key2, $array)) return false;
    if(($index1 = array_search($key1, $keys, $strict)) === false) return false;
    if(($index2 = array_search($key2, $keys, $strict)) === false) return false;
    if(!$preserve_keys) list($keys[$index1], $keys[$index2]) = array($key2, $key1);
    list($array[$key1], $array[$key2]) = array($array[$key2], $array[$key1]);
    return array_combine($keys, array_values($array));
}

For example:

$arr = array_swap($arr, 'grapefruit', 'pear');