js千分位加逗号

code

function toThousands(num) {
var numArr = num.split('.');
num = numArr[0];
var result = '';
while (num.length > 3) {
result = ',' + num.slice(-3) + result;
num = num.slice(0, num.length - 3);
}
if (num) { result = num + result; }
return result + '.' + numArr[1];
}