Commas as thousands separators in number in Javascript

 
For example, we want to display 1000 as 1,000.  JavaScript function  toLocaleString is used, example:
n=1000;

m=n.toLocaleString();

m will be 1,000 

If n is a string, we need to convert to number first

Number(n).toLocaleString();

toFixed(2) convert a number into a string, keeping only two decimals, we need to convert it to number when using  toLocaleString()
m = Number(n. toFixed(2)).toLocaleString();