Using Javascript, how do I make sure a date range is valid?

Question

In JavaScript, what is the best way to determine if a date provided falls within a valid range?

An example of this might be checking to see if the user input r

Answer 1

var myDate = new Date(2008, 9, 16);

// is myDate between Sept 1 and Sept 30?

var startDate = new Date(2008, 9, 1);
var endDate = new Date(2008, 9, 30);

if (startDate < myDate && myDate < endDate) {
    alert('yes');
    // myDate is between startDate and endDate
}

There are a variety of formats you can pass to the Date() constructor to construct a date. You can also construct a new date with the current time:

var now = new Date();

and set various properties on it:

now.setYear(...);
now.setMonth(...);
// etc

See http://www.javascriptkit.com/jsref/date.shtml or Google for more details.