current month start date and end date with formate in jquery

JavaScript
var date = new Date();
var firstDay = new Date(date.getFullYear(), date.getMonth(), 1);
var lastDay = new Date(date.getFullYear(), date.getMonth() + 1, 0);var lastday = function(y,m){
return  new Date(y, m +1, 0).getDate();
}
console.log(lastday(2014,0));
console.log(lastday(2014,1));
console.log(lastday(2014,11));

<html>
   <head>
      <title>JavaScript Dates</title>
   </head>
   <body>
      <script>
         var date = new Date();
         document.write("Current Date: " + date );
         var firstDay = new Date(date.getFullYear(), date.getMonth(), 1);
         document.write("<br>"+firstDay);
         var lastDay = new Date(date.getFullYear(), date.getMonth() + 1, 0);
         document.write("<br>"+lastDay);
      </script>
   </body>
</html>
Source

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