ELMAH: Only sending specific exception type via mail

Question

I have ELMAH set up for a webapp, logging exceptions to a SQL server.

I wish to have ELMAH send me an email too, but only when a specific exception is thrown (ie. MySpecialException).

ELMAH must still log all exceptions to SQL server.

I know you can do it programmatically in global.asax, but I'd prefer to use web.config.

So, how do I restrict ELMAH error mails to filter out everything but a specific exception type, using web.config?

UPDATE

The filter ended up looking like this:

<test>
    <and>
        <not>
            <is-type binding="Exception" type="MyApp.MySpecialException" />
        </not>
        <regex binding="FilterSourceType.Name" pattern="mail" caseSensitive="false"/>
    </and>
</test>

Answer 1

Its certainly possible to do. Check out the filtering documentation for elmah.

In particular look at the section Filtering By Source

<elmah>
...
<errorFilter>
    <test>
        <and>
            <equal binding="HttpStatusCode" value="404" type="Int32" />
            <regex binding="FilterSourceType.Name" pattern="mail" />
        </and>
    </test>
</errorFilter>