Webmaster Forum / ColdFusion / Advanced Techniques / September 2007

Not sure on Apache, but on IIS you can set up a custom error page for a 404
error.  This custom error page can be any file (including .cfm)  that is
accessible from the root of the site.  So, if you go into iis and set a custom
error for 404, you can point it to something like /404Handler.cfm, then create
the 404Handler.cfm template in the root of your website.  Inside this file you
can do what ever you like, including redirecting to the home page.  One of the
nice features of how iis handles 404 errors is that the URL of the page that
was requested will be stored in the CGI.query_string.  For example, if a user
types in http://www.yoursite.com/foobar.html and /foobar.html does not exist,
the user will be forwarded to /404Handler.cfm and CGI.query_string will be
404;/foobar.html.  

This is a very easy way to handle friendly URLs as well.  for example let's
say you have a user table that has a username and useid field.  Now let's also
say you have a profile.cfm themplate that takes in the URL variable called
userid, and then looks up the user and displays the user's profile.  Using the
method above, you can create a friendly URL like
http://www.yoursite.com/users/username, however you do not create a users
directory.  If a user types in this URL he/she would normally get a 404 error,
but since you redirected to the 404Handler.cfm, you can get the URL by saying
<cfset target=ListLast(cgi.query_string,";")>, then check  to see if target url
contains /users (<cfif target contains "/users">).  If it does, you can get the
username by saying <cfset username=ListLast(target,"/")>.  Once you have the
username you can then query the database to figure out what the userid is and
then redirect to profile.cfm.  It seems a little convoluted, but it works.

How about an onError method in Application.CFC for HTTP errors?

sswaka,
thanks for the info, but I am having a little trouble.  I created a
404_error.htm page for the site.  Went to IIS and identified the file as a 404
error.  Now if I type in a bad file name everything works. EXCEPT if the file
has a .cfm extention. If the file ends with .cfm, then I get a Cold Fusion
error for debugging.  I thought that because I had "Enable Robust Exception
Information" checked on, maybe that was the problem.  But I turned it off and I
still don't see me custom 404 error page if the bad file being called is a .cfm
file.

Any ideas?

I believe what you're looking for is configurable in the ColdFusion
Administrator.

In CF 7, this is configurable at the following location:
    Server Settings > Settings > Missing Template Handler

yup.  That did it, thanks!