js实现金额小写转大写

function convertCurrency(currencyDigits) {
    var MAXIMUM_NUMBER = 1000000000000.00;

    var CN_ZERO = "零";
    var CN_ONE = "壹";
    var CN_TWO = "贰";
    var CN_THREE = "叁";
    var CN_FOUR = "肆";
    var CN_FIVE = "伍";
    var CN_SIX = "陆";
    var CN_SEVEN = "柒";
    var CN_EIGHT = "捌";
    var CN_NINE = "玖";
    var CN_TEN = "拾";
    var CN_HUNDRED = "佰";
    var CN_THOUSAND = "仟";
    var CN_TEN_THOUSAND = "万";
    var CN_HUNDRED_MILLION = "亿";
    var CN_SYMBOL = "人民币";
    var CN_DOLLAR = "元";
    var CN_TEN_CENT = "角";
    var CN_CENT = "分";
    var CN_INTEGER = "整";

    var integral;    // integral part
    var decimal;     // decimal part
    var outputCharacters = "";    // result.
    var parts;
    var digits, radices, bigRadices, decimals;
    var zeroCount;
    var i, p, d;
    var quotient, modulus;

    if (currencyDigits != null) {
        currencyDigits = currencyDigits.toString();
        currencyDigits = currencyDigits.replace(/,/g, "");    // Remove comma delimiters. 
        currencyDigits = currencyDigits.replace(/^0+/, "");   // Trim zeros at the beginning. 

        if (Number(currencyDigits) < MAXIMUM_NUMBER) {
            if (Number(currencyDigits) < 0) {
                outputCharacters += "负";
                currencyDigits = Math.abs(Number(currencyDigits)).toString();
            }

            parts = currencyDigits.split("."); // separate the number by decimal point
            if (parts.length > 1) {
                integral = parts[0];
                decimal = parts[1];                        
                decimal = decimal.substr(0, 2);// two decimal places
            } else {
                integral = parts[0];
                decimal = "";
            }

            digits = new Array(CN_ZERO, CN_ONE, CN_TWO, CN_THREE, CN_FOUR, CN_FIVE, CN_SIX, CN_SEVEN, CN_EIGHT, CN_NINE);
            radices = new Array("", CN_TEN, CN_HUNDRED, CN_THOUSAND);
            bigRadices = new Array("", CN_TEN_THOUSAND, CN_HUNDRED_MILLION);
            decimals = new Array(CN_TEN_CENT, CN_CENT);

            if (Number(integral) > 0) {
                zeroCount = 0;
                for (i = 0; i < integral.length; i++) {
                    p = integral.length - i - 1;
                    d = integral.substr(i, 1);
                    quotient = p / 4;
                    modulus = p % 4;
                    if (d == "0") {
                        zeroCount++;
                    } else {
                        if (zeroCount > 0) {
                            outputCharacters += digits[0];
                        }
                        zeroCount = 0;
                        outputCharacters += digits[Number(d)] + radices[modulus];
                    }
                    if (modulus == 0 && zeroCount < 4) {
                        outputCharacters += bigRadices[quotient];
                    }
                }
                outputCharacters += CN_DOLLAR;
            }

            if (decimal != "") {
                for (i = 0; i < decimal.length; i++) {
                    d = decimal.substr(i, 1);
                    if (d != "0") {
                        outputCharacters += digits[Number(d)] + decimals[i];
                    }
                }
            }
            if (outputCharacters == "") {
                outputCharacters = CN_ZERO + CN_DOLLAR;
            }
            if (decimal == "") {
                outputCharacters += CN_INTEGER;
            }
            outputCharacters = "" + outputCharacters + "";
        }
    }
    return outputCharacters;
}