"Bill M." <wp*********@hotmail.com> wrote in message
news:6a**************************@msgid.meganewsse rvers.com...
How do pop-up blocker programs work? Do they intercept http transactions
and strip-out window.open() commands? Is there a single methodology?
Thanks
I have Internet Security 2003... It has a feature to block popups and
adverts... It is very successful, but not 100% successful.
I did some checks... note, I am a javascript newbie but I am a techie (with
several years of linux/unix and some windoze support behind me) so I think I
got a good distance...
First... part of the Firewall that comes with Internet Security 2003 and its
efforts to prevent popups is it scans all html as you surf and if it finds
reference to "banner" or "popup" it can end up either removing the
code/reference to the function or createing a similar named function after
the original named function so as the author's original one is not
used/called.
Thus, a javascript with /banner/ in the path will not be displayed - the
same with /banner.js or /banner.jpg It has other terms also written in, and
it has various website names too (like doubleclick.net) that are
automatically ignored.
Secondly, I found that when I do a View Source of some web pages, I get code
similar to the following sprinkled in there (normally immediately after
<head>)
<script language="JavaScript">
<!--
function SymError()
{
return true;
}
window.onerror = SymError;
var SymRealWinOpen = window.open;
function SymWinOpen(url, name, attributes)
{
return (new Object());
}
window.open = SymWinOpen;
//-->
</script>
This code turns up before </BODY>
<script language="JavaScript">
<!--
window.open = SymRealWinOpen;
//-->
</script>
I have visited
http://mail.yahoo.com then did a view source and extracted
the above just as an example - I don't know if difference code is inserted
pending on what website I visit.
Does that help you any?
randelld
