ASP.NET MVC URL重写与优化(进阶篇)-继承RouteBase玩转URL

http://www.xxx.com/category/showcategory?categoryid=0001&view=list&orderby=price&page=1
=>
http://www.xxx.com/category/0001

http://www.xxx.com/ca-categoryname

    public abstract class RouteBase
    {
        protected RouteBase();
        public abstract RouteData GetRouteData(HttpContextBase httpContext);
        public abstract VirtualPathData GetVirtualPath(RequestContext requestContext, RouteValueDictionary values);
    }

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web.Mvc;//需要添加引用，请使用3.0以上版本 
using System.Web.Routing;
using JohnConnor.Models;

namespace JohnConnor.Routing
{
    public class CategoryUrlProvider:RouteBase
    {
        public override RouteData GetRouteData(System.Web.HttpContextBase httpContext)
        {
            return null;//断点1
        }

        public override VirtualPathData GetVirtualPath(RequestContext requestContext, RouteValueDictionary values)
        {
            return null;//断点2
        }
    }
}

    public static void RegisterRoutes(RouteCollection routes)
        {
            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
            routes.Add(new JohnConnor.Routing.CategoryUrlProvider());//分类规则
            routes.MapRoute("Home", "", new { controller = "Home", action = "Index"});//主页
        }

public override RouteData GetRouteData(System.Web.HttpContextBase httpContext)
        {
            var data = new RouteData(this, new MvcRouteHandler());
            data.Values.Add("controller", "Home");
            data.Values.Add("action", "Index");
            return data;
        }

<a href="@Url.Action("Index", "Home")">首页</a>

values["controller"]="Home"；
values["action"]="Index"；

<a href="http://localhost:1234/">首页</a>

 public override VirtualPathData GetVirtualPath(RequestContext requestContext, RouteValueDictionary values)
        {
            return  new VirtualPathData(this, "This-is-a-Test-URL");
        }

 public override RouteData GetRouteData(System.Web.HttpContextBase httpContext)
        {
            var virtualPath = httpContext.Request.AppRelativeCurrentExecutionFilePath + httpContext.Request.PathInfo;//获取相对路径

　　　　　　　virtualPath = virtualPath.Substring(2).Trim(‘/‘);//此时URL会是～/ca-categoryname，截取后面的ca-categoryname

            if (!virtualPath.StartsWith("ca-"))//判断是否是我们需要处理的URL，不是则返回null，匹配将会继续进行。
                return null;

            var categoryname = virtualPath.Split(‘-‘).Last();//截取ca-前缀后的分类名称

　　　　　　　//尝试根据分类名称获取相应分类，忽略大小写
            var category = CategoryManager.AllCategories.Find(c => c.CategoeyName.Equals(categoryname,StringComparison.OrdinalIgnoreCase));

            if (category == null)//如果分类是null，可能不是我们要处理的URL，返回null，让匹配继续进行
                return null;

            //至此可以肯定是我们要处理的URL了
            var data = new RouteData(this, new MvcRouteHandler());//声明一个RouteData，添加相应的路由值
            data.Values.Add("controller", "Category");
            data.Values.Add("action", "ShowCategory");
            data.Values.Add("id", category.CategoeyID);

            return data;//返回这个路由值将调用CategoryController.ShowCategory(category.CategoeyID)方法。匹配终止
        }

public override VirtualPathData GetVirtualPath(RequestContext requestContext, RouteValueDictionary values)
        {
            //判断请求是否来源于CategoryController.Showcategory(string id),不是则返回null,让匹配继续
            var categoryId = values["id"] as string;

            if (categoryId == null)//路由信息中缺少参数id，不是我们要处理的请求，返回null
                return null;

            //请求不是CategoryController发起的，不是我们要处理的请求，返回null
            if (!values.ContainsKey("controller") || !values["controller"].ToString().Equals("category",StringComparison.OrdinalIgnoreCase))
                return null;
            //请求不是CategoryController.Showcategory(string id)发起的，不是我们要处理的请求，返回null
            if (!values.ContainsKey("action") || !values["action"].ToString().Equals("showcategory", StringComparison.OrdinalIgnoreCase))
                return null;

            //至此，我们可以确定请求是CategoryController.Showcategory(string id)发起的，生成相应的URL并返回
            var category = CategoryManager.AllCategories.Find(c => c.CategoeyID == categoryId);

            if (category == null)
                throw new ArgumentNullException("category");//找不到分类抛出异常

            var path = "ca-" + category.CategoeyName.Trim();//生成URL

            return new VirtualPathData(this, path.ToLowerInvariant());
        }

<a href="/ca-nokia">Nokia</a>
<a href="/ca-iphone">iPhone</a>
<a href="/ca-anycall">Anycall</a>