Wednesday, August 6, 2008

Formatting numbers

This one comes up a lot - how to format a number with commas and decimal points? Just pass your number into this function and it will return a formatted string. Including commas is optional.


function formatNumbers(num:Number, comma:Boolean):String {
// return a zero value if num is not valid
if (isNaN(num)) {
return "0.00";
}
// round num to the nearest 100th
num = Math.round(num * 100) / 100;
// convert num to a string
var num_str:String = String(num);
// seperate any decimals from the whole numbers
var num_array = num_str.split(".");
// if there are no decimals add them using "00"
if (num_array[1] == undefined) {
num_array[1] = "00";
}
// if the decimals are too short, add an extra "0"
if (num_array[1].length == 1) {
num_array[1] += "0";
}
// separate whole numbers with commas
// if required (comma = true)
if (comma) {
var whole_array:Array = new Array();
var start:Number;
var end:Number = num_array[0].length;
while (end > 0) {
start = Math.max(end - 3, 0);
whole_array.unshift(num_array[0].slice(start, end));
end = start;
}
num_array[0] = whole_array.join(",");
}
// construct a return string joining
// the whole numbers with the decimals
return (num_array.join("."));
}
trace(formatNumbers(1234));
// outputs 1234.00
trace(formatNumbers(1234.56));
// outputs 1234.56
trace(formatNumbers(1234.5, true));
// outputs 1,234.50
trace(formatNumbers(-1234.56789, true));
// outputs -1,234.57

3 comments:

Sarah said...

This works great! Thanks!

glosrfc said...

No problem...glad you found it useful!

Anonymous said...

neat! thx!