Convert SharePoint Date in to ConvertDateToISO - And Use for Custom Save

-------------Code -------------------------------------------

function ConvertDateToISO(dtDate)
{
//*************************************************
//Converts Javascript dtDate to ISO 8601 standard for compatibility with SharePoint lists
//Inputs: dtDate = Javascript date format (optional)
//*************************************************
//alert("InISOCOnversion");
  var d;
  if (dtDate != null)  {
     //Date value supplied
    
     d = new Date(dtDate);
  }
  else  {
     //No date supplied, Create new date object
     d = new Date();
  }
  //Generate ISO 8601 date/time formatted string
  var s = "";
  //alert(d.getFullYear());
   if(d.getFullYear)
   {
   //alert("FullYear");
         s += d.getFullYear() + "-";
    }
    else
    {
     //alert("getyear");
     var year= d.getYear() + 1900;
     s += year + "-";
       
    }
  //s += d.getYear() + "-";
  s += d.getMonth() + 1 + "-";
  s += d.getDate();
  s += "T" + d.getHours() + ":";
  s += d.getMinutes() + ":";
  //Replace the "Z" below with the required
  //time zone offset (eg "+10:00" - Australian EST)
  s += d.getSeconds() + "Z";
  //Return the ISO8601 date string
  return s;
}