Working with dates in JavaScript

var d = new Date("2015-03-25");

function dateFormat(date){

      var dd = date.getDate();
      var mm = date.getMonth()+1; //January is 0!
      var yyyy = date.getFullYear();

      if(dd<10) {
          dd='0'+dd;
      }

      if(mm<10) {
          mm='0'+mm;
      }

      date = dd + '-' + mm + '-' + yyyy;
      // date = yyyy+'-'+mm+'-'+dd;

  return date;
}

var today = new Date();
var day_7 = new Date();
day_7.setDate(day_7.getDate() - 7);

var day_8 = new Date();
day_8.setDate(day_8.getDate() - 8);

var day_14 = new Date();
day_14.setDate(day_14.getDate() - 15);

console.log(dateFormat(today));
console.log(dateFormat(day_7));
console.log(dateFormat(day_8));
console.log(dateFormat(day_14));

25.11.2016
18.11.2016
17.11.2016
10.11.2016

var l_data11 = "2016-11-30";
var l_data22 = "2016-04-30";

var l_data1 = new Date(l_data11); // 2016-11-30
var l_data2 = new Date(l_data22); // 2016-04-30



console.log("l_data1 XXXX");
console.log(dateToSQLDate(dateFormat(l_data1)));

console.log("l_data2 XXXX");
console.log(dateToSQLDate(dateFormat(l_data2)));



function dateToSQLDate(data){
    return data.substring(0, 10);
}

var theBigDay = new Date(1962, 6, 7); // 1962-07-07
theBigDay.setDate(24);  // 1962-07-24
theBigDay.setDate(32);  // 1962-08-01
theBigDay.setDate(22);  // 1962-08-22