PHP function array_merge is nice in that you can easily merge one (or more) arrays into a single array with a single call of the function. The keys are retained, but only if they’re not numeric keys(!).
"hi"); $array2 = array(3 => "data"); $result = array_merge($array1, $array2); ?> Result: Array (  => hi  => data )
Perhaps this is the behavior you want. But what if you want to retain the original numeric keys?