URL路由

原文 : http://quickstarts.asp.net/3-5-extensions/mvc/URLRouting.aspx

1. 介绍

2. 定义URL路由
URL路由包括一个URL模式定义,在模式定义中,"{}"定义占位符,"/"和"."分割各个字符串.
当URL请求字符串被URL模式解析时,占位符和具体的值组成"键值对".
一般,URL路由在Global.asax文件的Application_Start方法中被定义.
示例代码:

protected void Application_Start(object sender, EventArgs e)
{
    RegisterRoutes(RouteTable.Routes);
}
public static void RegisterRoutes(RouteCollection routes)
{
routes.Add(new Route("Category/{action}/{categoryName}",new CategoryRouteHandler() ));
}
3. 为路由参数设置默认值.
若不设置默认值,则URL路由要求所有占位符都必须赋值才能匹配.
示例代码:
public static void RegisterRoutes(RouteCollection routes)
{
  routes.Add(new Route("Category/{action}/{categoryName}", new CategoryRouteHandler())
                {
Defaults = new RouteValueDictionary 
                                    {
                                        {"categoryName", "food"}, {"action", "show"}
                                    }
                }
  );
}
4. 捕获未知数量的参数.
使用"*"通配符,如:"query/{queryname}/{*queryvalues}",
使用它可以匹配"/query/select/bikes/onsale", 则queryvalues = "bikes/onsale".
5. 为URL模式添加约束.
示例代码:
public static void RegisterRoutes(RouteCollection routes)
{
    routes.Add(new Route("{locale}/{year}" , new ReportRouteHandler())
                    {
Constraints = new RouteValueDictionary 
                                            {
                                                {"locale", "{a-z}{2}-{A-Z}{2}"},{year, @"d{4}"}
                                            }
                    }
    );
}
6. 使用URL路由信息创建链接.
示例代码:
HyperLink1.NavigateUrl = RouteTable.Routes.GetVirtualPath
  (context,
  new RouteValueDictionary { 
    { "categoryName", "beverages" }, 
    {"action", "summarize" }}
  ).VirtualPath;
将获得一个包含"Category/summarize/beverages"的超链接.