JavaScript: Format Number to Money

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JavaScript: Format Number to Money

These days I was in need of a function in javascript to transform number to currency. And in my research I ended up finding this code:

// Extend the default Number object with a formatMoney() method:
// usage: someVar.formatMoney(decimalPlaces, symbol, thousandsSeparator, decimalSeparator)
// defaults: (2, "$", ",", ".")
Number.prototype.formatMoney = function(places, symbol, thousand, decimal) {
	places = !isNaN(places = Math.abs(places)) ? places : 2;
	symbol = symbol !== undefined ? symbol : "$";
	thousand = thousand || ",";
	decimal = decimal || ".";
	var number = this, 
	    negative = number < 0 ? "-" : "", i = parseInt(number = Math.abs(+number || 0).toFixed(places), 10) + "", j = (j = i.length) > 3 ? j % 3 : 0;
	return symbol + negative + (j ? i.substr(0, j) + thousand : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + thousand) + (places ? decimal + Math.abs(number - i).toFixed(places).slice(2) : "");
};

// Default usage and custom precision/symbol :
var revenue = 12345678;
console.log(revenue.formatMoney()); // $12,345,678.00
console.log(revenue.formatMoney(0, "HK$ ")); // HK$ 12,345,678

// European formatting:
var price = 4999.99;
console.log(price.formatMoney(2, "€", ".", ",")); // €4.999,99

// It works for negative values, too:
console.log( (-500000).formatMoney(0, "£ ") ); // £ -500,000

Removing Money Format:

var price = (12345.99).formatMoney(); // "$12,345.99"

// Remove non-numeric chars (except decimal point/minus sign):
priceVal = parseFloat(price.replace(/[^0-9-.]/g, '')); // 12345.99

Non-Number.prototype version:

// To set it up as a global function:
function formatMoney(number, places, symbol, thousand, decimal) {
	number = number || 0;
	places = !isNaN(places = Math.abs(places)) ? places : 2;
	symbol = symbol !== undefined ? symbol : "$";
	thousand = thousand || ",";
	decimal = decimal || ".";
	var negative = number < 0 ? "-" : "", i = parseInt(number = Math.abs(+number || 0).toFixed(places), 10) + "", j = (j = i.length) > 3 ? j % 3 : 0;
	return symbol + negative + (j ? i.substr(0, j) + thousand : "") + i.substr(j).replace(/(\d{3})(?=\d)/g, "$1" + thousand) + (places ? decimal + Math.abs(number - i).toFixed(places).slice(2) : "");
}

// To create it as a library method:
myLibrary.formatMoney = function(number, places, symbol, thousand, decimal) {
	/* as above */
}

// Example usage:
formatMoney(54321); // $54,321
myLibrary.formatMoney(12345, 0, "£ "); // £ 12,345

Reference and author of the code:
http://www.josscrowcroft.com/2011/code/format-unformat-money-currency-javascript/