php金额如何转大写

/**
*数字金额转换成中文大写金额的函数
*String Int $num 要转换的小写数字或小写字符串
*return 大写字母
*小数位为两位
**/
function num_to_rmb($num){
 $c1 = "零壹贰叁肆伍陆柒捌玖";
 $c2 = "分角元拾佰仟万拾佰仟亿";
 //精确到分后面就不要了，所以只留两个小数位
 $num = round($num, 2); 
 //将数字转化为整数
 $num = $num * 100;
 if (strlen($num) > 10) {
 return "金额太大，请检查";
 } 
 $i = 0;
 $c = "";
 while (1) {
 if ($i == 0) {
 //获取最后一位数字
 $n = substr($num, strlen($num)-1, 1);
 } else {
 $n = $num % 10;
 }
 //每次将最后一位数字转化为中文
 $p1 = substr($c1, 3 * $n, 3);
 $p2 = substr($c2, 3 * $i, 3);
 if ($n != '0' || ($n == '0' && ($p2 == '亿' || $p2 == '万' || $p2 == '元'))) {
 $c = $p1 . $p2 . $c;
 } else {
 $c = $p1 . $c;
 }
 $i = $i + 1;
 //去掉数字最后一位了
 $num = $num / 10;
 $num = (int)$num;
 //结束循环
 if ($num == 0) {
 break;
 } 
 }
 $j = 0;
 $slen = strlen($c);
 while ($j < $slen) {
 //utf8一个汉字相当3个字符
 $m = substr($c, $j, 6);
 //处理数字中很多0的情况,每次循环去掉一个汉字“零”
 if ($m == '零元' || $m == '零万' || $m == '零亿' || $m == '零零') {
 $left = substr($c, 0, $j);
 $right = substr($c, $j + 3);
 $c = $left . $right;
 $j = $j-3;
 $slen = $slen-3;
 } 
 $j = $j + 3;
 } 
 //这个是为了去掉类似23.0中最后一个“零”字
 if (substr($c, strlen($c)-3, 3) == '零') {
 $c = substr($c, 0, strlen($c)-3);
 }
 //将处理的汉字加上“整”
 if (empty($c)) {
 return "零元整";
 }else{
 return $c . "整";
 }
}
echo num_to_rmb(23000000.00); //贰仟叁佰万元整