2019独角兽企业重金招聘Python工程师标准>>> 
// 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) : "");};如下便是一些转换实例：
// Default usage and custom precision/symbol :var revenue = 12345678;alert(revenue.formatMoney()); // $12,345,678.00alert(revenue.formatMoney(0, "HK$ ")); // HK$ 12,345,678// European formatting:var price = 4999.99;alert(price.formatMoney(2, "€", ".", ",")); // €4.999,99// It works for negative values, too:alert((-500000).formatMoney(0, "£ ")); // £ -500,000
