In a DotNetNuke site how do I bypass a 404 error? - http-status-code-404

Question

I have a site -- example.com. It has static pages -- example.com/signup, example.com/faq, etc.
However, I want to be able to have "example.com/some-search-term". Of course, there is no page "some-search-term".
I tried installing a custom module on the 404 error page that would take the query string and display some info based on that search criteria. However, I still get a 404 error "HTTP404: NOT FOUND - The server has not found anything matching the requested URI (Uniform Resource Identifier).
GET - http://example.com/some-search-term." and the page is blank.
I can debug my module when the 404 page is triggered and see that everything is working fine but the final results are not displayed.
Any ideas?

Answer 1

For something like this I would suggest using IIS rewrite rules or rewritemaps. You can do this via the web.config or separate files that the web.config points to. If you setup a redirect for each term, you'll be good to go.
EG: in Web.config
<rewrite>
<rewriteMaps configSource="fmrewrites.config" />
<rules configSource="fmrules.config" />
</rewrite>
And within the fmrewrites.congig
<?xml version="1.0" encoding="utf-8"?>
<rewriteMaps>
<rewriteMap name="FmRedirects">
<add key="www.siteexample.com/," value="https://www.siteexample.com/" />
</rewriteMap>
</rewriteMaps>
Or within the fmrules.config
<?xml version="1.0" encoding="utf-8"?>
<rules>
<clear />
<rule name="FmRewrites" stopProcessing="true">
<match url=".*" />
<conditions logicalGrouping="MatchAny" trackAllCaptures="false">
<add input="{FmRedirects:{HTTP_HOST}{REQUEST_URI}}" pattern="(.+)" ignoreCase="true" />
</conditions>
<action type="Redirect" url="{C:1}" appendQueryString="false" />
</rule>
</rules>
You can read up on a lot of this via MS Docs.

Answer 2

I solved this a different way.
DNN provides a default 404 page. I simply added a custom module that evaluates the status code on Page_Load():
_rcode = Response.StatusCode;
if (_rcode == 404) //we're on our 404 page
{
Response.Clear();
Server.ClearError();
}
The module then does a few database lookups on the query string to see if there are any matches. If there are, it redirects to the appropriate page. If nothing matches, then I generate a 404 error.
I was trying to keep everything on the 404 page but I couldn't. Since the page "example.com/some-search-term" doesn't actually exist, some page components aren't available -- IsPostBack, ViewState, Session, etc. -- so it was difficult to generate a page that worked. Even setting the Response.StatusCode to 200 did not work.
Ultimately, I was trying to prevent google from seeing a 404 error unless I wanted it to. This seems to have worked.