MVC custom route 02-implement IRouteConstraint to limit the Controller name

By implementing the IRouteConstraint interface, you can restrict a control name. This article focuses on custom constraints. For more information, see:

MVC custom route 01-why do I need custom routing?

using System.Web.Mvc;

using System.Web.Routing;

using MvcApplication2.Extension;

namespace MvcApplication2

{

    public class RouteConfig

    {

        public static void RegisterRoutes(RouteCollection routes)

        {

            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

// Default

            routes.MapRoute(

                name: "Default",

                url: "{controller}/{action}/{id}",

                defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }

            );

        }

    }

}

Effect

□Implement the IRouteConstraint Interface

using System;

using System.Web.Routing;

namespace MvcApplication2.Extension

{

    public class ExcludeController : IRouteConstraint

    {

        private readonly string _controller;

        public ExcludeController(string controller)

        {

            _controller = controller;

        }

        public bool Match(System.Web.HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values, RouteDirection routeDirection)

        {

// If the controller value obtained in the route is equal to the value set by the constraint, false is returned.

            return !string.Equals(values["controller"].ToString(), _controller, StringComparison.OrdinalIgnoreCase);

        }

    }

}

□Route adding Constraints

using System.Web.Mvc;

using System.Web.Routing;

using MvcApplication2.Extension;

namespace MvcApplication2

{

    public class RouteConfig

    {

        public static void RegisterRoutes(RouteCollection routes)

        {

            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

// Default

            routes.MapRoute(

                name: "Default",

                url: "{controller}/{action}/{id}",

                defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },

                constraints: new { controller = new ExcludeController("RentalProperties") }

            );

        }

    }

}

Effect

As you can see, when you add custom constraints, the controller with the RentalProperties name will be restricted.