o_19mgorv9t13a3ko71fev19l81mqa.pdf

{
}
}
}
httpMethod = new HttpMethodConstraint("GET"),
id = new CompoundRouteConstraint(new IRouteConstraint[]
new AlphaRouteConstraint(),
new MinLengthRouteConstraint(6)
})
},
new[] { "URLsAndRoutes.Controllers" });
In the listing, I have constrained the first route so that it will match only requests made from browsers whose user-agent string
contains Chrome. If the route matches, then the request will be sent to the Index action method in the Home controller
defined in the AdditionalControllers folder, irrespective of the structure and content of the URL that has been
requested. The URL pattern consists of just a catchall segment variable, which means that the values for the controller and
action segment variables will always be taken from the defaults and not the URL itself.
The second route will match all other requests and target controllers in the Controllers folder, subject to the type and
value constraints I applied in the previous section. The effect of these routes is that one kind of browser always ends up at the
same place in the application. You can see this in Figure 15-13, which shows the effect of navigating to the app using Google
Chrome.
Figure 15-13. Navigating to the app using the Google Chrome browser
Figure 15-14 shows the result of navigating to the example application using Internet Explorer. (Notice that I have to add a third
segment that contains six or more alpha characters to make the second route match the URL because of the constraints I applied
in the last section.)
Figure 15-14. Navigating to the app using Internet Explorer
Note To be clear, because this is the kind of thing I get angry letters about, I am not suggesting that you restrict your
application so that it supports only one kind of browser. I used user-agent strings solely to demonstrate custom route constraints
and believe in equal opportunities for all browsers. I really hate Web sites that try to force their preference for browsers on users.
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