How to get current date and time based on users timezones

Hi All,

In our instance my time zone is US Eastern so when I am getting any date and time field value it is giving in US eastern. But my systems time zone is India so when I used "new Date()" it is giving value in India's timezone. So I am not able to compare those two field values.Please see the below code I have written.

function onChange(control, oldValue, newValue, isLoading) {

  if (isLoading || newValue == '') {

  return;

  }

var stDate=new Date(getDateFromFormat(g_form.getValue('RequestedStartDate'),g_user_date_time_format));

var now = new Date();

  //alert(stDate);

  //alert(now);

  if(stDate < now)

  {

        alert('System open time should be greater than or equal to current date and time');

  g_form.clearValue('RequestedStartDate');

  //return false;

  }

}