Date manipulation with VBScript

Beyond simply displaying the date, VBScript provides a number of functions
that allow you to manipulate dates. The DateAdd(interval, number, date)
and DateDiff(interval, date1, date2) are helpful functions that are
usually left for the developer to write.

Both functions require you to pass an interval argument. This argument
specifies the time interval to add to the date or to compare the dates.
The DateAdd(interval, number, date) function returns a date that is the
specified number of intervals from the given date. The DateDiff(interval,
date1, date2) function returns the number of intervals between date1 and
date2.

There is also a handy function called DateSerial(year, month, day) that
returns a variant of the Date subtype. This function is very useful when
you need to create a date (such as Christmas) for use in the DateDiff()
function.

The following code shows these three functions in action:

<% dToday = Date() %>
In 10 days it will be
     <%= DateAdd("d", 10, dToday) %>
<P>
<% dChristmas = DateSerial(1998,12,25) %>

Christmas is just <%= DateDiff("d", dToday, dChristmas) %> days away!

From--ZD Journals' Active Server Developers Journal