MVC Extensions

While the automatic parameters validation provided by SEO Extensions may be more than welcomed in new web sites and applications, you may want to adjust or turn it off for existing projects or for specific cases, in order to resemble the standard ASP.NET MVC routing behavior. The good news is that the parameters validation system is completely configurable by way of the

TypeDefaultConstraintRegistry

class. Whenever SEO Extensions needs to validate a route parameter for an incoming request, it checks the aforementioned

Constraint

property first, and, should it be missing, checks the

TypeDefaultConstraintRegistry

class to see if a default constraint for the type has been specified there.

In fact, SEO Extensions comes with a set of built-in constraints, automatically registered for the most used types exposed by the .NET Framework, including numeric types, booleans, GUIDs and enumerations.

If you need to get rid of the existing parameter validation logic for one of your route parameters, for example, you may want to set the

Constraint

property of its

Route.Param

attribute to

null

:

            public class MyController : Controller
            {
                [Route.Action("~/foo")]
                public ActionResult Foo([Route.Param(Constraint = null)] int bar)
                {
                    return Content("Baz!");
                }
            }
        

Replacing the parameters validation logic for your entire web site, by the way, could easily be done in your application class (global.asax) by calling the

Register()

static method of the

TypeDefaultConstraintRegistry

(or the

Unregister()

static method to completely remove the validation logic for a given type):

Excerpt from the application class (global.asax.cs):

        public static void RegisterRoutes(RouteCollection routes)
        {
            // ...

            TypeDefaultConstraintRegistry.Register(typeof(UInt32), "\d+");

            // ...
        }
        

Moreover, SEO Extensions allows to easily add your own default constraints to be used during parameter validations! Should you have a custom business class you need to pass as a route parameter, for example, you may easily define a custom constraint and register it for your whole application, using the aforementioned

Register()

method. This way, the framework will automatically validate your parameters before executing the target actions using your own type constraints.