This is the last tricky cookies hurdle: By default, a cookie can
be read only
by
HTML pages that sit on the same Web server and in the same directory
as
the page that set the cookie.
For example, if you
have
a
JavaScript on
"http://chimp.webmonkey.com/food/bananas/banana_puree.htm"
that
asks
people for their names, you might want to access a given name
on
another
one of your Web pages, such as the
homepage (http://chimp.webmonkey.com/.) To allow this, you have to set
the "path"
of the cookie. The "path" sets the top level directory from which a
cookie can
be read.
Set the path of a cookie to the top-level directory of
your
Web
pages, and the
cookie is readable by all your Web pages.
Do this by
adding path=/; to your cookie. If you just wanted the
cookie readable
solely in the "food" directory, you'd add path=/food;
to your
cookie.
A second hitch is that some Web sites have lots of
little
domains. For example, We might have pages at
"chimp.website.com,"
"gorilla.website.com," and "ape.website.com."
By default, if a Web
page on "chimp.website.com"
sets a cookie, only
pages on
"chimp.webmonkey.com" can read it. If we wanted
all the machines
in the
"webmonkey.com" domain to read the cookie, we'd have to add
"domain=webmonkey.com" to the cookie. Don't get clever though.
Pages
at
"republicans.com"
can't set or read cookies from
"democrats.com."
To
put all the above together — set a cookie on the
Web page
"http://chimp.webmonkey.com/food/bananas/banana_puree.htm"
that
we want
to be readable by all pages — we'd have to
do
this:
function setCookie()
{
var the_name = prompt("What's your name?","");
var the_cookie = "cookie_puss=" + escape(the_name) + ";" ;
var the_cookie = the_cookie + "path=/;";
var the_cookie = the_cookie + "domain=webmonkey.com;";
document.cookie = the_cookie;
}
And
so ends the cookies lesson.
Let's review what we've learned so far
and
then go onto a final
exercise.
next page»
