Showing different pages with the same url

When a user logs in, set a cookie with a short expiry time...

Then you can query the cookie & display content based upon their login status...

Of course, this will require that your users permit cookies!

>>display content based upon their login status.

This is the question. How do I change/select the page to display with the same URL?

e.g.
If a user is logged in, show index1.aspx
If a user is not logged in show index2.aspx.

I have no problem checking the log in status of the user. What I want to know is how to show a different page using the same url.

Note: I do NOT want to redirect the user to a different address.

Following reference shows how to set & test cookies as well as conditional code:

http://www.quirksmode.org/js/cookies.html

Look for the section named readCookie...
where it says:

var x = readCookie('ppkcookie1')
if (x) {
	[do something with x]
}

Select allOpen in new window

replace "do something with x" (you can have one page's code)
and add an "else" clause for the opposite condition...

>>replace "do something with x" (you can have one page's code)

My question is about the "do something" after the If statement.

Sorry if my question was not clear, so let me rephrase the question:

Let's say I want to show a different page on my homepage depending on the time of the day.

If time is between 0:00 to 11:59, show "AMPage.aspx" on my homepage. If time is between 12:00 to 23:59, show "PMPage.aspx" on my homepage.

Note: I do not want to redirect it to a different address.

Is this how it is usually done? I think that it is a common situation to show a different site for guest and logged-in users.

e.g. experts-exchange.com

Also, is it possible to deny access to some pages by directly typing in the URL? i.e. I don't want to allow access to AMPage.aspx by directly typing in "http://mysite.com/AMPage.aspx"