Javascript format date / time

For instance you can create a function like:

  var date = new Date(value);

            var yr = date.getFullYear();
          //  var month = date.getMonth() < 10 ? '0' + date.getMonth() : date.getMonth() + 1;
            var day = date.getDate() < 10 ? '0' + date.getDate() : date.getDate();
         
            var month = date.getMonth() + 1;
            var selected = yr + '-' + month + '-' + day;

or

function formatDate(date) {

  var hours = date.getHours();

  var minutes = date.getMinutes();

  var ampm = hours >= 12 ? 'pm' : 'am';

  hours = hours % 12;

  hours = hours ? hours : 12; // the hour '0' should be '12'

  minutes = minutes < 10 ? '0'+minutes : minutes;

  var strTime = hours + ':' + minutes + ' ' + ampm;

  return date.getMonth()+1 + "/" + date.getDate() + "/" + date.getFullYear() + "  " + strTime;

}

var d = new Date();

var e = formatDate(d);

alert(e);