js金额转换为大写

function DX(n) {
        if (n == 0) {
            return "零";
        }
        if (!/^(\+|-)?(0|[1-9]\d*)(\.\d+)?$/.test(n))
            return "数据非法";
        var unit = "仟佰拾亿仟佰拾万仟佰拾元角分", str = "";
        n += "00";
        var a = parseFloat(n);
        if (a < 0) {
            n = n.substr(1);
        }
        var p = n.indexOf('.');
        if (p >= 0) {
            n = n.substring(0, p) + n.substr(p + 1, 2);
        }

        unit = unit.substr(unit.length - n.length);

        for (var i = 0; i < n.length; i++)
            str += '零壹贰叁肆伍陆柒捌玖'.charAt(n.charAt(i)) + unit.charAt(i);
        if (a > 0) {
            return str.replace(/零(仟|佰|拾|角)/g, "零").replace(/(零)+/g, "零").replace(/零(万|亿|元)/g, "$1").replace(/(亿)万|壹(拾)/g, "$1$2").replace(/^元零?|零分/g, "").replace(/元$/g, "元整");

        } else {

            return "负" + str.replace(/零(仟|佰|拾|角)/g, "零").replace(/(零)+/g, "零").replace(/零(万|亿|元)/g, "$1").replace(/(亿)万|壹(拾)/g, "$1$2").replace(/^元零?|零分/g, "").replace(/元$/g, "元整");
        }
    }