How do I do a Date comparison in Javascript? [duplicate]

Answer 1

I would rather use the Date valueOf method instead of === or !==

Seems like === is comparing internal Object's references and nothing concerning date.

Answer 2

function fn_DateCompare(DateA, DateB) {     // this function is good for dates > 01/01/1970

    var a = new Date(DateA);
    var b = new Date(DateB);

    var msDateA = Date.UTC(a.getFullYear(), a.getMonth()+1, a.getDate());
    var msDateB = Date.UTC(b.getFullYear(), b.getMonth()+1, b.getDate());

    if (parseFloat(msDateA) < parseFloat(msDateB))
      return -1;  // lt
    else if (parseFloat(msDateA) == parseFloat(msDateB))
      return 0;  // eq
    else if (parseFloat(msDateA) > parseFloat(msDateB))
      return 1;  // gt
    else
      return null;  // error
}

Answer 3

if (date1.getTime() > date2.getTime()) {
    alert("The first date is after the second date!");
}

Reference to Date object