[MVC]Lowercase Route URLs in ASP.NET MVC

转载：http://goneale.com/2008/12/19/lowercase-route-urls-in-aspnet-mvc/

Lowercase Route URL's in ASP.NET MVC

For anybody interesting in having ruby on rails style routes; or follow a lowercase URL pattern (mysite.com/member/profile/goneale) which most web 2.0 sites seem to be following, check out the below code cited and enhanced from this article (http://www.makiwa.com/index.php/2008/05/31/lowercase-mvc-route-urls/).

Firstly you will need a RouteExtensions.cs file, or named anything you like with the following (compatible as at ASP.NET MVC RC1):

using System;
using System.Web.Mvc;
using System.Web.Routing;
 
namespace MyMvcApplication.App.Helpers
{
    public class LowercaseRoute : System.Web.Routing.Route
    {
        public LowercaseRoute(string url, IRouteHandler routeHandler)
            : base(url, routeHandler) { }
        public LowercaseRoute(string url, RouteValueDictionary defaults, IRouteHandler routeHandler)
            : base(url, defaults, routeHandler) { }
        public LowercaseRoute(string url, RouteValueDictionary defaults, RouteValueDictionary constraints, IRouteHandler routeHandler)
            : base(url, defaults, constraints, routeHandler) { }
        public LowercaseRoute(string url, RouteValueDictionary defaults, RouteValueDictionary constraints, RouteValueDictionary dataTokens, IRouteHandler routeHandler)
            : base(url, defaults, constraints, dataTokens, routeHandler) { }
 
        public override VirtualPathData GetVirtualPath(RequestContext requestContext, RouteValueDictionary values)
        {
            VirtualPathData path = base.GetVirtualPath(requestContext, values);
 
            if (path != null)
                path.VirtualPath = path.VirtualPath.ToLowerInvariant();
 
            return path;
        }
    }
 
    public static class RouteCollectionExtensions
    {
        public static void MapRouteLowercase(this RouteCollection routes, string name, string url, object defaults)
        {
            routes.MapRouteLowercase(name, url, defaults, null);
        }
 
        public static void MapRouteLowercase(this RouteCollection routes, string name, string url, object defaults, object constraints)
        {
            if (routes == null)
                throw new ArgumentNullException("routes");
 
            if (url == null)
                throw new ArgumentNullException("url");
 
            var route = new LowercaseRoute(url, new MvcRouteHandler())
            {
                Defaults = new RouteValueDictionary(defaults),
                Constraints = new RouteValueDictionary(constraints)
            };
 
            if (String.IsNullOrEmpty(name))
                routes.Add(route);
            else
                routes.Add(name, route);
        }
    }
}

Then a using reference in your Global.asax.cs file to the above class, and you’re all set to create a lowercase route.
You can see a below example of a lowercase route and anytime this route is called your URL will be lowercased.

            routes.MapRouteLowercase(
                "Default", // Route name
                "{controller}/{action}/{id}", // URL with parameters
                new {controller = "Home", action = "index", id = ""} // Parameter defaults
                );

and optionally if you are interested in converting any incoming URL’s to lowercase (manually typed by the user or called links) you can use this in your Application_BeginRequest() method (Remember, this is not needed for lowercase routes themselves, the code above will handle that):

        protected void Application_BeginRequest(Object sender, EventArgs e)
        {
            // If upper case letters are found in the URL, redirect to lower case URL.
            // Was receiving undesirable results here as my QueryString was also being converted to lowercase.
            // You may want this, but I did not.
            //if (Regex.IsMatch(HttpContext.Current.Request.Url.ToString(), @"[A-Z]") == true)
            //{
            //    string LowercaseURL = HttpContext.Current.Request.Url.ToString().ToLower();
 
            //    Response.Clear();
            //    Response.Status = "301 Moved Permanently";
            //    Response.AddHeader("Location", LowercaseURL);
            //    Response.End();
            //}
 
            // If upper case letters are found in the URL, redirect to lower case URL (keep querystring the same).
            string lowercaseURL = (Request.Url.Scheme + "://" + HttpContext.Current.Request.Url.Authority + HttpContext.Current.Request.Url.AbsolutePath);
            if (Regex.IsMatch(lowercaseURL, @"[A-Z]"))
            {
                lowercaseURL = lowercaseURL.ToLower() + HttpContext.Current.Request.Url.Query;
 
                Response.Clear();
                Response.Status = "301 Moved Permanently";
                Response.AddHeader("Location", lowercaseURL);
                Response.End();
            }
        }