Amount formatted comma separated

Using toLocaleString is a simple and good method. I didn't know that writing functions by myself was complicated before.

	  console.log((-8888.8888888).toLocaleString('zh', { maximumFractionDigits: 3, useGrouping: false }));
	  console.log((-8888.8888888).toLocaleString();
  let money=(3000).toLocaleString();
     console.log(money)

More toLocaleString usage reference

toLocaleString detailed usage

Amount division function written by myself

function fmoney(s, n) {  //s传入金额，n保留位数
	n = n > 0 && n <= 20 ? n : 0;
	s = parseFloat((s + "").replace(/[^\d\.-]/g, "")).toFixed(n) + "";
	var l = s.split(".")[0].split("").reverse(), r = s.split(".")[1];
	let t = "";
	for (let i = 0; i < l.length; i++) {
		t += l[i] + ((i + 1) % 3 == 0 && (i + 1) != l.length ? "," : "");
	}
	if(n==0){
		return t.split("").reverse().join("");
	}
	else{
		return t.split("").reverse().join("") + "." + r;
	}
	
}