100字范文 > ASP.NET MVC系列：UrlRouting

ASP.NET MVC系列：UrlRouting

时间：2020-05-11 22:46:30

1. URLRouting简介

URL(Uniform Resource Locator)，统一资源定位器，是用于完整描述Internet上的网页或其他资源地址的一种标识方法。

URL一般可以由6部分组成，格式如下：

protocol :// hostname [:port] [/path] [?parameters] [#fragment]

URL各部分说明：

protocol 协议：可以是HTTP(超文本传输协议)、FTP(文件传输协议)和HTTPS(安全超文本传输协议)。

hostname 主机名：指在互联网中存放资源的服务器DNS主机名或IP地址。

port 端口号：该选项是一个小于66536的正整数，是各服务器或协议约定的通信端口。

path 路径：用来表示一个Web站点中的目录或文件资源的地址。

parameters 参数列表：参数形式为以=隔开的键/值对，多个参数之间用&连接。

fragment 信息片段：用于直接定位到页面中的某个锚点标记。

2. URLRouting与URLRewrite区别

URLRouting是一组从URL到请求处理程序间的映射规则，将URL映射到能够处理业务需求的Action上。URLRouting是一个独立的类库System.Web.Routing.dll。

URLRouting为将URL映射到Controller的Action上，处理流程图如下：

URLRewrite为将URL映射到具体的文件资源上，处理流程图如下：

3. MVC中使用及自定义URLRouting规则

在Web.config文件中与Routing有关的的节点：sytem.web.httpModules，system.web.httpHandlers，system.webserver.modules，system.webserver.handlers。

MVC应用程序第一次启动时，将调用Global.asax中Application_Start()方法。每个 MVC应用程序至少需要定义一个URLRouting来指明应用程序如何处理请求，复杂的应用程序可以包含多个URLRouting。

3.1App_Start/RouteConfig.cs

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.Mvc;using System.Web.Routing;namespace Libing.Portal.Web{public class RouteConfig{public static void RegisterRoutes(RouteCollection routes){routes.IgnoreRoute("{resource}.axd/{*pathInfo}");routes.MapRoute(name: "Default",url: "{controller}/{action}/{id}",defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional });}}}

Global.asax

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.Mvc;using System.Web.Routing;namespace Libing.Portal.Web{public class MvcApplication : System.Web.HttpApplication{protected void Application_Start(){AreaRegistration.RegisterAllAreas();RouteConfig.RegisterRoutes(RouteTable.Routes);}}}

3.2 Route类

RouteCollection对象以静态属性的方式声明在RouteTable的属性Routes中，RouteCollection对象存储的是Route类的实例。一个完整的Route类实例需要有URL、默认值、约束、数据密钥及路由处理程序等属性。

public RouteValueDictionary Constraints { get; set; }public RouteValueDictionary DataTokens { get; set; }public RouteValueDictionary Defaults { get; set; }public IRouteHandler RouteHandler { get; set; }public string Url { get; set; }

3.3 Route类属性

name：

路由名称，必须是唯一不能重复。

url：

在Route类中，属性URL是一个字符串，用于描述请求中URL的格式。该字符串可能不完全是一个实际的URL，可以带一些{}标记的占位符，使用占位符可以从URL中提取数据。如：

"{controller}/{action}/{id}"

{controller}参数的值用于实例化一个处理请求的控制类对象，{action}参数的值用于指明处理当前请求将调用控制器中的方法。

defaults：

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

constraints：

new { controller = @"^\w+", action = @"^\w+", id = @"\d+" }

namespaces：

Route.DataTokens属性，获取或设置传递到路由处理程序但未用于确定该路由是否匹配 URL 模式的自定义值。

3.4 自定义URLRouting规则

分页：

routes.MapRoute(

"Page",

"{controller}/List/Page/{page}",

new { controller = "Home", action = "List", page = UrlParameter.Optional },

new { page = @"\d*" }

);

public string List(int? page)

{

return page == null ? "1" : page.ToString();

}

本地化多语言Routing：

public static void RegisterRoutes(RouteCollection routes){routes.IgnoreRoute("{resource}.axd/{*pathInfo}");// 本地化 routes.MapRoute(name: "Localization",url: "{lang}/{controller}/{action}/{id}",defaults: new { lang = "zh-CN", controller = "Home", action = "Index", id = UrlParameter.Optional },constraints: new { lang = "^[a-zA-Z]{2}(-[a-zA-Z]{2})?$" });routes.MapRoute(name: "Default",url: "{controller}/{action}/{id}",defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional });}

分页Routing:

routes.MapRoute(name: "PagedList",url: "{controller}/Page/{page}",defaults: new { controller = "Product", action = "Index" },constraints: new { page = @"\d+" });

Blog根据日期Routing：

routes.MapRoute(name: "blog",url: "blog/{user}/{year}/{month}/{day}",//defaults: new { controller = "Blog", action = "Index", day = 1 },defaults: new RouteValueDictionary{{"controller", "Blog"},{"action", "Index"},{"day", 1}},constraints: new { year = @"\d{4}", month = @"\d{1,2}", day = @"\d{1,2}" });

Reports根据年月Routing：

routes.MapRoute(name: "Reports",url: "Reports/{year}/{month}",defaults: new { controller = "Reports", action = "Index" },constraints: new { year = @"\d{4}", month = @"\d{1,2}" });

3.5 创建Routing约束

使用正则表达式来指定路由约束：

routes.MapRoute(name: "Product",url: "Product/{ProductID}",defaults: new { controller = "Product", action = "Details" },constraints: new { ProductID = @"\d+" });

3.6 自定义Routing约束

通过实现IRouteConstraint接口来实现自定义路由。

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.Routing;namespace Libing.Portal.Web.Models.Constraints{public class LocalhostConstraint : IRouteConstraint{public bool Match(HttpContextBase httpContext,Route route,string parameterName,RouteValueDictionary values,RouteDirection routeDirection){return httpContext.Request.IsLocal;}}}

routes.MapRoute(name: "Admin",url: "Admin/{action}",defaults: new { controller = "Admin" },constraints: new { isLocal = new LocalhostConstraint() });

自定义浏览器访问Routing约束：

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.Routing;namespace Libing.Portal.Web.Models.Constraints{public class UserAgentConstraint:IRouteConstraint{private string _userAgent;public UserAgentConstraint(string userAgent){_userAgent = userAgent;}public bool Match(HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values, RouteDirection routeDirection){return httpContext.Request.UserAgent != null && httpContext.Request.UserAgent.Contains(_userAgent);}}}

routes.MapRoute(name: "Chrome",url: "{*catchall}",defaults: new { controller = "Home", action = "Index" },constraints: new { customConstraint = new UserAgentConstraint("Chrome") });

自定义用户个人网址Routing：

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.Routing;using Libing.Portal.Web.Models;namespace Libing.Portal.Web.Models.Constraints{public class UserConstraint : IRouteConstraint{public bool Match(HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values, RouteDirection routeDirection){using (PortalContext context = new PortalContext()){string userRouteValue = values["user"].ToString();var user = (from u in context.Userswhere u.UserName == userRouteValueselect u).FirstOrDefault();return user != null;}}}}

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