Change array key without changing order

Question

You can \"change\" the key of an array element simply by setting the new key and removing the old:

$array[$newKey] = $array[$oldKey];
unset($array[$oldKey]);         


        

Answer 1

We are using this function for changing multiple array keys within an array keeping the order:

function replace_keys($array, $keys_map) {
    $keys = array_keys($array);
    foreach($keys_map as $old_key=>$new_key){
        if (false === $index = array_search($old_key, $keys)) {
            continue;
        }
        $keys[$index] = $new_key;
    }
    return array_combine($keys, array_values($array));
}

You can pass an array as $keys_map, like this:

$keys_map=array("old_key_1"=>"new_key_1", "old_key_2"=>"new_key_2",...)

This solution is based on Kristian one.

Answer 2

Something like this may also work:

$langs = array("EN" => "English", 
        "ZH" => "Chinese", 
        "DA" => "Danish",
        "NL" => "Dutch", 
        "FI" => "Finnish", 
        "FR" => "French",
        "DE" => "German");
$json = str_replace('"EN":', '"en":', json_encode($langs));
print_r(json_decode($json, true));

OUTPUT:

Array
(
    [en] => English
    [ZH] => Chinese
    [DA] => Danish
    [NL] => Dutch
    [FI] => Finnish
    [FR] => French
    [DE] => German
)