js格式化金额

function number_format(number, decimals, dec_point, thousands_sep) {
    /*
    * 参数说明：
    * number：要格式化的数字
    * decimals：保留几位小数
    * dec_point：小数点符号
    * thousands_sep：千分位符号
    * */
    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) {
            return "" + n.toFixed(prec);
         }
  
     s = (prec ? toFixedFix(n, prec) : '' + Math.round(n)).split('.');
     var re = /(-?\d+)(\d{3})/;
     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);
 }

测试var num=number_format(1234567.089, 2, ".", ",");//1,234,567.09

function number_format(number, decimals, dec_point, thousands_sep) {
          /*
          * 参数说明：
          * number：要格式化的数字
          * decimals：保留几位小数
          * dec_point：小数点符号
          * thousands_sep：千分位符号
          * */
          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);
     }
     number_format(1234567.089, 2, ".", ",");//1,234,567.08