JS将数字格式化成货币（钱）格式

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 = (a = i.length) > 3 ? a % 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) : "");
}

// 把12345.67变成美元格式，$12,345.67
console.log(formatMoney(12345.67));
// 把12345.67变成人民币格式，并保留3位小数，￥12,345.670
console.log(formatMoney(12345.67, 3, "￥"));
// 把$12,345.67变成纯数字12345.67
console.log(parseFloat('$12,345.67'.replace(/[^0-9-.]/g, '')));