js中价格格式化

//转换格式化###,###,##.00
function number_format(num){
num = parseFloat(num);
var SUM="";
var sumFol = num.toFixed(2);
var sumtotalStr = sumFol;
var sumEndStr = sumtotalStr.slice(sumtotalStr.indexOf("."));
var sumStr = sumtotalStr.slice(0,sumtotalStr.indexOf("."));
if(num.toString().length <= 3) return num;
if(sumStr.toString().length > 3){
var count=0;
if (sumStr.toString().length % 3 == 0) {
count = sumStr.toString().length/3;
}else{
count = (sumStr.toString().length-sumStr.toString().length%3)/3;
}
var text = "";
for(i=0;i<count;i++) {
if((count-i-1)*3+sumStr.toString().length%3!=0) {
text=","+sumStr.slice((count-i-1)*3+sumStr.toString().length%3,(count-i-1)*3+sumStr.toString().length%3+3)+text;
}else {
text=sumStr.slice((count-i-1)*3+sumStr.toString().length%3,(count-i-1)*3+sumStr.toString().length%3+3)+text;
}
}
SUM = sumStr.slice(0,sumStr.toString().length % 3)+text+sumEndStr;
return SUM;
}
return sumFol ;
}