JavaScript FormatNumber function Implementation method _javascript skills

Since there is no such function in JavaScript, how do we implement it? Below I give this function, you can put: <script language=javascript src= "formatnumber.js" To add your HTML page, you can also use
<!--#include file= "formatnumber.js"--> Add to your ASP page;
? Include ("Formatnumber.js")?> Add to the PHP page;
<%@ #include file= "Formatnumber.js"%> to join the JSP page.
This formatnumber function is as follows:
<script language=javascript>
<!--
function FormatNumber (Srcstr,nafterdot) {
var Srcstr,nafterdot;
var Resultstr,nten;
Srcstr = "" +srcstr+ "";
strlen = Srcstr.length;
Dotpos = Srcstr.indexof (".", 0);
if (Dotpos = = 1) {
ResultStr = srcstr+ ".";
for (i=0;i<nafterdot;i++) {
ResultStr = resultstr+ "0";
}
return resultstr;
}
else{
if ((strlen-dotpos-1) >= Nafterdot) {
Nafter = Dotpos + Nafterdot + 1;
Nten = 1;
for (j=0;j<nafterdot;j++) {
Nten = nten*10;
}
ResultStr = Math.Round (parsefloat (SRCSTR) *nten)/nten;
return resultstr;
}
else{
ResultStr = Srcstr;
For (i=0;i< (Nafterdot-strlen + dotpos + 1); i++) {
ResultStr = resultstr+ "0";
}
return resultstr;
}
}
}