JavaScript 动态将数字金额转化为中文大写金额

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 = "人民币"; 
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("Empty input!"); 
return ""; 
} 
if (currencyDigits.match(/[^,.\d]/) != null) { 
//alert("Invalid characters in the input string!"); 
return ""; 
} 
if ((currencyDigits).match(/^((\d{1,3}(,\d{3})*(.((\d{3},)*\d{1,3}))?)|(\d+(.\d+)?))$/) == null) { 
//alert("Illegal format of digit number!"); 
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("您输入的金额太大，请重新输入!"); 
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[i]; 
} 
} 
} 
// 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; 
}