$array["1"] = "someval1";
$array["2"] = "someval2";
$array["3"] = "someval3";
$array["10"] = "someval4";
$array["100"] = "someval5";
$array["20"] = "someval6";
$array["200"] = "someval7";
$array["30"] = "someval8";
$array["300"] = "someval9";
var_dump($array);
ksort($array, SORT_STRING);
var_dump($array);