Comma format a number - actionscript

Question

I need to format numbers with commas as thousand seperators, for example:
1234 = 1,234
1234.50 = 1,234.50
12345.60 = 12,345.60
123456.70 = 123,456.70
1234567.80 = 1,234,567.80
etc etc
This needs to work for numbers with decimal values or without
i.e. both 1234567.80 and 1234567
This is for Actionscript 2 in a Coldfusion / Flash application, so normal actionscript is being used. I have seen a couple of solutions on the net but none quite do the trick.
So far I have the function below, but it is not formatting correctly when decimals are provided.For example: 21898.5 becomes 2,188,8.5.
Please could you help me find the bug or offer an alternative solution that fulfils the requriements.
Thanks
_global.NumberFormat = function(theNumber)
{
var myArray:Array;
var numberPart:String;
var decPart:String;
var result:String = '';
var numString:String = theNumber.toString();
if(theNumber.indexOf('.') > 0)
{
myArray = theNumber.split('.');
numberPart = myArray[0];
decPart = myArray[1];
}
else
{
numberPart = numString;
}
while (numString.length > 3)
{
var chunk:String = numString.substr(-3);
numString = numString.substr(0, numString.length - 3);
result = ',' + chunk + result;
}
if (numString.length > 0)
{
result = numString + result;
}
if(theNumber.indexOf('.') > 0)
{
result = result + '.' + decPart;
}
//alert('Result: ' + result);
return result;
}

Answer 1

You could try this:
_global.NumberFormat = function(numString)
{
numString = String(numString);
var index:Number = numString.indexOf('.');
var decimal:String;
if(index > 0) {
var splitByDecimal:Array = numString.split(".");
//return NumberFormat(splitByDecimal[0])+"."+splitByDecimal[1];
numString = splitByDecimal[0];
decimal = splitByDecimal[1];
} else if(index === 0) {
return "0"+numString;
}
var result:String = '';
while (numString.length > 3 ) {
var chunk:String = numString.substr(-3);
numString = numString.substr(0, numString.length - 3);
result = ',' + chunk + result;
}
result = numString + result;
if(decimal) result = result + "." + decimal;
return result;
}
It splits the number by the decimal if present(compensating for an illegal '.01234' if required), and uses recursion so call itself on the split element.
For your example numbers this traces:
1,234
1,234.50
12,345.60
123,456.70
1,234,567.80
Just for fun
This is why your original code didn't work:
After creating a string representation of the number (var numString:String = theNumber.toString();) you then carried on using the actual number rather than the string version.
After assigning a value to number part you then continued to perform operations on numString rather than numberPart.
A corrected version looks like this:
_global.NumberFormat = function(theNumber)
{
var myArray:Array;
var numberPart:String;
var decPart:String;
var result:String = '';
var numString:String = theNumber.toString();
if(numString.indexOf('.') > 0)
{
myArray = numString.split('.');
numberPart = myArray[0];
decPart = myArray[1];
}
else
{
numberPart = numString;
}
while (numberPart.length > 3)
{
var chunk:String = numberPart.substr(-3);
numberPart = numberPart.substr(0, numberPart.length - 3);
result = ',' + chunk + result;
}
if (numberPart.length > 0)
{
result = numberPart + result;
}
if(numString.indexOf('.') > 0)
{
result = result + '.' + decPart;
}
//alert('Result: ' + result);
return result;
}

Answer 2

public static function formatNumberString(value:Number,separator:String):String {
var result:String = "";
var digitsCount:Number = value.toString().length;
separator = separator || ",";
for (var i:Number = 0; i < digitsCount; i++) {
if ((digitsCount - i) % 3 == 0 && i != 0) {
result += separator;
}
result += value.toString().charAt(i);
}
return result;
}

Answer 3

Try this out, works fine for me:
var largeNumber:String=new String(1000000.999777);
var fAr:Array=largeNumber.split(".");
var reg:RegExp=/\d{1,3}(?=(\d{3})+(?!\d))/;
while(reg.test(fAr[0]))
fAr[0]=fAr[0].replace(reg,"$&,");
var res:String=fAr.join(".");
trace(res);
Trace: 1,000,000.999777