登录后如何更改到用户名的路由？

您需要添加一条路由来覆盖具有用户名的案例。

public static void RegisterRoutes(RouteCollection routes)
{
    routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

    routes.MapRoute(
        name: "Username_Default",
        url: "{username}/{controller}/{action}/{id}",
        defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },
        constraints: new { username = new OwinUsernameConstraint() }
    );

    routes.MapRoute(
        name: "Default",
        url: "{controller}/{action}/{id}",
        defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional }
    );
}

但是，要使其正常工作，您将需要在URL中添加文字字符串以将该段标识为用户名（即username-{username}\），或者需要进行限制以仅允许数据库中的用户名。这是后者的一个示例：

using MvcUsernameInUrl.Models;
using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Web;
using System.Web.Caching;
using System.Web.Routing;

namespace MvcUsernameInUrl
{
    public class OwinUsernameConstraint : IRouteConstraint
    {
        private object synclock = new object();

        public bool Match(HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values, RouteDirection routeDirection)
        {
            if (parameterName == null)
                throw new ArgumentNullException("parameterName");
            if (values == null)
                throw new ArgumentNullException("values");

            object value;
            if (values.TryGetValue(parameterName, out value) && value != null)
            {
                string valueString = Convert.ToString(value, CultureInfo.InvariantCulture);
                return this.GetUsernameList(httpContext).Contains(valueString);
            }
            return false;
        }

        private IEnumerable<string> GetUsernameList(HttpContextBase httpContext)
        {
            string key = "UsernameConstraint.GetUsernameList";
            var usernames = httpContext.Cache[key];
            if (usernames == null)
            {
                lock (synclock)
                {
                    usernames = httpContext.Cache[key];
                    if (usernames == null)
                    {
                        // Retrieve the list of usernames from the database
                        using (var db = ApplicationDbContext.Create())
                        {
                            usernames = (from users in db.Users
                                            select users.UserName).ToList();
                        }

                        httpContext.Cache.Insert(
                            key: key,
                            value: usernames,
                            dependencies: null,
                            absoluteExpiration: Cache.NoAbsoluteExpiration,
                            slidingExpiration: TimeSpan.FromSeconds(15),
                            priority: CacheItemPriority.NotRemovable,
                            onRemoveCallback: null);
                    }
                }
            }

            return (IEnumerable<string>)usernames;
        }
    }
}

注意：我强烈建议像在示例中那样为此使用缓存，因为路由约束会在每个请求上运行，并且在每个请求上都命中数据库是不好的。这样做的缺点是，用户名注册后最多需要15秒才能生效。除了将记录添加到数据库之外，还可以通过在注册新帐户时更新缓存（以线程安全的方式）（以线程安全的方式）来解决此问题，这将使其立即在路由约束中可用。

然后，只需在用户登录时进行302重定向即可。您可以在全局过滤器中进行此操作。

using System.Web;
using System.Web.Mvc;

namespace MvcUsernameInUrl
{
    public class RedirectLoggedOnUserFilter : IActionFilter
    {
        public void OnActionExecuting(ActionExecutingContext filterContext)
        {
            var routeValues = filterContext.RequestContext.RouteData.Values;
            bool isLoggedIn = filterContext.HttpContext.User.Identity.IsAuthenticated;
            bool requestHasUserName = routeValues.ContainsKey("username");

            if (isLoggedIn && !requestHasUserName)
            {
                var userName = filterContext.HttpContext.User.Identity.Name;
                // Add the user name as a route value
                routeValues.Add("username", userName);

                filterContext.Result = new RedirectToRouteResult(routeValues);
            }
            else if (!isLoggedIn && requestHasUserName)
            {
                // Remove the user name as a route value
                routeValues.Remove("username");

                filterContext.Result = new RedirectToRouteResult(routeValues);
            }
        }

        public void OnActionExecuted(ActionExecutedContext filterContext)
        {
            // Do nothing
        }
    }
}

用法

public class FilterConfig
{
    public static void RegisterGlobalFilters(GlobalFilterCollection filters)
    {
        filters.Add(new RedirectLoggedOnUserFilter());
        filters.Add(new HandleErrorAttribute());
    }
}

MVC会在生成URL时自动重用请求中的路由值，因此无需更改任何ActionLinks包含的内容username。

这是在GitHub上使用MVC5，OWIN和ASP.NET Identity的工作演示。