Question

I have two fields that a user will fill in, one is a begin date, the other is the end date.

I want to alert the user if the end date is less than the begin date.

The values will be in this format: YYYYMMDD (20101209)

So I need this to fire an alert (if the begin date is greater than the end date) to the user once both fields are filled in, so it won’t alert them until both fields are filled in.

Also, these two fields are hidden fields, because I am using the altFormat, altField of jQuery’s datepicker.

the id and name’s of the hidden fields are: begin_date, end_date

Also need help firing the function after both fields are filled.

Answer 1

function compareDates(d1, d2) {
    var date1 = new Date(d1);
    var date2 = new Date(d2);

    if(date1.getTime() > date2.getTime()) {
        alert("Start Date is greater than End Date");
    }
}

There may be a shorter way, I’m no JS expert.