PHP menambahkan elemen ke awal array asosiatif

$arr1 = array('key0' => 'value0') + $arr1;

-------------- OR ------------------

<?php
$arr = array('key1' => 'value1', 'key2' => 'value2');
$arr = array_merge(array('key0' => 'value0'), $arr);
Lokesh003