WebForms使用System.Web.Routing

老赵同学写过 在Web应用程序开发过程中利用ASP.NET MVC框架的实战技巧 ，Routing现在可以作为URLRewriting技术的替代者，出现在asp.net mvc框架中，将它应用于WebForms上也是很简单的，可以到codeplex上下载ASP.NET MVC WebFormRouting Demo 。

实现的原理也是很简单的：

1、创建一个自定义的实例化你的页面的 IRouteHandler  

public class WebFormRouteHandler : IRouteHandler {

public WebFormRouteHandler(string virtualPath)     : this(virtualPath, true) {    
        }    
    
public WebFormRouteHandler(string virtualPath, bool checkPhysicalUrlAccess)
 { 
            if (virtualPath == null)
  { 
                throw new ArgumentNullException("virtualPath");   
            } 

            if (!virtualPath.StartsWith("~/")) { 
                throw new ArgumentException("virtualPath must start with a tilde slash: /"~//"", "virtualPath"); 
            }  

            this.VirtualPath = virtualPath; 
            this.CheckPhysicalUrlAccess = checkPhysicalUrlAccess; 
        } 
    
        /// <summary>
        /// This is the full virtual path (using tilde syntax) to the WebForm page.
        /// </summary>
        /// <remarks>
        /// Needs to be thread safe so this is only settable via ctor.
        /// </remarks>
   
        public string VirtualPath { get; private set; }  

        /// <summary>
        /// Because we're not actually rewriting the URL, ASP.NET's URL Auth will apply
        /// to the incoming request URL and not the URL of the physical WebForm page.
        /// Setting this to true (default) will apply URL access rules against the
        /// physical file. 
        /// </summary>
        /// <value>True by default</value>
        public bool CheckPhysicalUrlAccess { get; set; } 
 
        public IHttpHandler GetHttpHandler(RequestContext requestContext) {  
            string virtualPath = GetSubstitutedVirtualPath(requestContext);  38: 
            if(this.CheckPhysicalUrlAccess && !UrlAuthorizationModule.CheckUrlAccessForPrincipal

(virtualPatrequestContext.HttpContext.User, requestContext.HttpContext.Request.HttpMethod))  
                throw new SecurityException();  
 
            var page = BuildManager.CreateInstanceFromVirtualPath(virtualPath, typeof(Page)) as IHttpHandler; 
            if(page != null) { 
                //Pages that don't implement IRoutablePage won't have the RequestContext
                //available to them. Can't generate outgoing routing URLs without that context.
                var routablePage = page as IRoutablePage;
                if(routablePage != null)   
                    routablePage.RequestContext = requestContext;  
            }  
            return page;  
        } 
  
        /// <summary>
        /// Gets the virtual path to the resource after applying substitutions based on route data.
        /// </summary>
        /// <param name="requestContext"></param>
        /// <returns></returns>
        public string GetSubstitutedVirtualPath(RequestContext requestContext) {  
            if (!VirtualPath.Contains("{")) 
                return VirtualPath;  
 
            //Trim off ~/
            string virtualPath = VirtualPath.Substring(2);

            Route route = new Route(virtualPath, this); 
            VirtualPathData vpd = route.GetVirtualPath(requestContext, requestContext.RouteData.Values); 
            if (vpd == null)   
                return VirtualPath; 
            return "~/" + vpd.VirtualPath; 
        }  70: 
    }
2、使用自定义的 IRouteHandler注册一个新的Routes

public class Global : System.Web.HttpApplication   
    {   
        protected void Application_Start(object sender, EventArgs e)   
        {  
            RegisterRoutes(RouteTable.Routes);   
        }  

        public static void RegisterRoutes(RouteCollection routes)  
        {  
            //We are intentionally creating this backdoor as a demonstration of
            //bad security practices.
            routes.MapWebFormRoute("Secret", "BackDoor", "~/Admin/SecretPage.aspx", false);  
            routes.MapWebFormRoute("Blocked", "FrontDoor", "~/Admin/SecretPage.aspx", true);  
            //Even though we are not checking physical url access in this route, it should still block because the incoming 
            //request url would start with /Admin.
            routes.MapWebFormRoute("Admin", "Admin/{*anything}", "~/Admin/SecretPage.aspx", false);  
            routes.MapWebFormRoute("Named", "foo/bar", "~/forms/blech.aspx"); 
            routes.MapWebFormRoute("Numbers", "one/two/three", "~/forms/haha.aspx"); 
            //Maps any requests for /haha/*.aspx to /forms/hahah.aspx
            routes.MapWebFormRoute("Substitution", "haha/{filename}", "~/forms/haha.aspx");  
        }   
    }

相关文章:

 <span id="ctl00_ArticleTopHeader_ArticleTitle" class="ArticleTopTitle">Fight 404 errors with ASP.NET Routing :<a href="http://www.codeproject.com/KB/aspnet/routing404.aspx">http://www.codeproject.com/KB/aspnet/routing404.aspx</a></span>

msdn杂志文章：
使用 ASP.NET Web 窗体路由：http://msdn.microsoft.com/zh-cn/magazine/2009.01.extremeaspnet.aspx