PHP轉換字符串編碼

<?php
function phpcharset($data, $to) {
	if(is_array($data)) {
		foreach($data as $key => $val) {
			$data[$key] = phpcharset($val, $to);
		}
	} else {
		$encode_array = array('ASCII', 'UTF-8', 'GBK', 'GB2312', 'BIG5');
		$encoded = mb_detect_encoding($data, $encode_array);
		$to = strtoupper($to);
		if($encoded != $to) {
			$data = mb_convert_encoding($data, $to, $encoded);
		}
	}
	return $data;
}
?>