JS实现数字转换为货币汉字大写数字

<script>
        function Chinese(num) {
            if (!/^\d*(\.\d*)?$/.test(num)) throw (new Error(-1, "Number is wrong!"));
            var AA = new Array("零", "壹", "贰", "叁", "肆", "伍", "陆", "柒", "捌", "玖");
            var BB = new Array("", "拾", "佰", "仟", "萬", "億", "圆", "");
            var CC = new Array("角", "分", "厘");
            var a = ("" + num).replace(/(^0*)/g, "").split("."), k = 0, re = "";
            for (var i = a[0].length - 1; i >= 0; i--) {
                switch (k) {
                    case 0: re = BB[7] + re; break;
                    case 4: if (!new RegExp("0{4}\\d{" + (a[0].length - i - 1) + "}$").test(a[0]))
                            re = BB[4] + re; break;
                    case 8: re = BB[5] + re; BB[7] = BB[5]; k = 0; break;
                }
                if (k % 4 == 2 && a[0].charAt(i) == "0" && a[0].charAt(i + 2) != "0") re = AA[0] + re;
                if (a[0].charAt(i) != 0) re = AA[a[0].charAt(i)] + BB[k % 4] + re; k++;
            }
            if (a.length > 1) {
                re += BB[6];
                for (var i = 0; i < a[1].length; i++) {
                    re += AA[a[1].charAt(i)] + CC[i];
                    if (i == 2) break;
                }
                if (a[1].charAt(0) == "0" && a[1].charAt(1) == "0") {
                    re += "元整";
                }
            } else {
                re += "元整";
            }
            return re;
        }
        document.write(Chinese(1)); //壹元整
    </script>