Is there a way to check if a date is less than 1 hour ago like this?

// old date

var olddate = new Date("February 9, 2012, 12:15");



// current date

var currentdate = new Date();



if (olddate >= currentdate - 1 hour) {

    alert("newer than 1 hour");

else {

    alert("older than 1 hour");

}

Also, different question - is there a way to add hours to a date like this?

var olddate = new Date("February 9, 2012, 12:15") + 15 HOURS; // output: February 10, 2012, 3:15