ES6給金額添加千位分隔符

static number_format(number, decimals, dec_point, thousands_sep) {
/*
* 參數說明：
* number：要格式化的數字
* decimals：保留幾位小數
* dec_point：小數點符號
* thousands_sep：千分位符號
* */
number = (number + ‘’).replace(/[^0-9±Ee.]/g, ‘’);
var n = !isFinite(+number) ? 0 : +number,
prec = !isFinite(+decimals) ? 0 : Math.abs(decimals),
sep = (typeof thousands_sep === ‘undefined’) ? ‘,’ : thousands_sep,
dec = (typeof dec_point === ‘undefined’) ? ‘.’ : dec_point,
s = ‘’,
toFixedFix = function (n, prec) {
var k = Math.pow(10, prec);
return ‘’ + Math.floor(n * k) / k;
};
s = (prec ? toFixedFix(n, prec) : ‘’ + Math.floor(n)).split(’.’);
var re = /(-?\d+)(\d{3})/;
//console.log(s)
while (re.test(s[0])) {
s[0] = s[0].replace(re, “$1” + sep + “$2”);
}

    if ((s[1] || '').length < prec) {
        s[1] = s[1] || '';
        s[1] += new Array(prec - s[1].length + 1).join('0');
    }
    return s.join(dec);

}