javascript实现数字转大写金额的函数

<SCRIPT type="text/javascript" Charset="GB2312">
function convertCurrency(currencyDigits) {
// Constants:
var MAXIMUM_NUMBER = 99999999999.99;
// Predefine the radix characters and currency symbols for output:
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 = "￥:";
var CN_SYMBOL="";
var CN_DOLLAR = "元";
var CN_TEN_CENT = "角";
var CN_CENT = "分";
var CN_INTEGER = "整";

// Variables:
var integral; // Represent integral part of digit number.
var decimal; // Represent decimal part of digit number.
var outputCharacters; // The output result.
var parts;
var digits, radices, bigRadices, decimals;
var zeroCount;
var i, p, d;
var quotient, modulus;

// Validate input string:
currencyDigits = currencyDigits.toString();
if (currencyDigits == "") {
alert("请输入要转换的数字!");
return "";
}
if (currencyDigits.match(/[^,.\d]/) != null) {
alert("数字中含有非法字符!");
return "";
}
if ((currencyDigits).match(/^((\d{1,3}(,\d{3})*(.((\d{3},)*\d{1,3}))?)|(\d+(.\d+)?))$/) == null) {
alert("错误的数字格式!");
return "";
}

// Normalize the format of input digits:
currencyDigits = currencyDigits.replace(/,/g, ""); // Remove comma delimiters.
currencyDigits = currencyDigits.replace(/^0+/, ""); // Trim zeros at the beginning.
// Assert the number is not greater than the maximum number.
if (Number(currencyDigits) > MAXIMUM_NUMBER) {
alert("超出转换最大范围!");
return "";
}

// Process the coversion from currency digits to characters:
// Separate integral and decimal parts before processing coversion:
parts = currencyDigits.split(".");
if (parts.length > 1) {
integral = parts[0];
decimal = parts[1];
// Cut down redundant decimal digits that are after the second.
decimal = decimal.substr(0, 2);
}
else {
integral = parts[0];
decimal = "";
}
// Prepare the characters corresponding to the digits:
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);
// Start processing:
outputCharacters = "";
// Process integral part if it is larger than 0:
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;
}
// Process decimal part if there is:
if (decimal != "") {
for (i = 0; i < decimal.length; i++) {
d = decimal.substr(i, 1);
if (d != "0") {
outputCharacters += digits[Number(d)] + decimals;
}
}
}
// Confirm and return the final output string:
if (outputCharacters == "") {
outputCharacters = CN_ZERO + CN_DOLLAR;
}
if (decimal == "") {
outputCharacters += CN_INTEGER;
}
outputCharacters = CN_SYMBOL + outputCharacters;
return outputCharacters;
}
</SCRIPT>
<INPUT id=Digits name=Digits size="15" value="1000001" > <INPUT id=Convert onclick="Result.value = convertCurrency(Digits.value);" type=button value=Convert name=Convert height="185659256"> <INPUT id=Result size=30 name=Result >