Question

I’m using ASP.NET routing to map URLs to some arbitrary number of sections to my site. They will all be handled by the same page, though I want to have different URLs. For example

http://site.com/blog for my blog section
http://site.com/mysection for mysection etc.

There can be any number of those sections, but they will all be handled by Lister.aspx.
I also have another page that handles the content, named ContentView.aspx which shows off content. My route is as follows: (cats is list of categories)

cats.ForEach(c =>
        {
            table.Add(new Route(c.ShortName, new PageRouteHandler("~/Lister.aspx?cat=" + c.ID), ));
            table.Add(new Route(c.ShortName + "/{id}", new PageRouteHandler("~/ContentView.aspx")));
            table.Add(new Route(c.ShortName + "/{id}/{title}", new PageRouteHandler("~/ContentView.aspx")));
        });

Let’s say I have a blog post with ID 123 and title hello:
A user can access it by http://site.com/blog/123/hello
They can also use just the ID http://site.com/blog/123
As you may guess, I want http://site.com/blog to point to the lister page instead of a content viewer, and I also need the category ID to distinguish which category (blog or mycategory or anything else that was created dynamically) I should display. I’m trying to pass the category ID to the querystring, the lister page is called, but with no query string. Why is this behavior, and how can I send my category ID to the lister page?

Answer 1

I would suggest creating your own RouteHandler that implements IRouteHandler which you could then pass a separate parameter to its constructor (the category ID).

Then in the GetHttpHandler you could then pass that ID on to the Page using HttpContext.

Something like:

public class CategoryRouteHandler : IRouteHandler 
{
   private string _virtualPath;
   private string _category;

   public CategoryRouteHandler(string virtualPath, string category)
   {
       _virtualPath = virtualPath;
       _category = category;
   }

   public IHttpHandler GetHttpHandler(RequestContext requestContext) 
   {
        var handler = BuildManager.CreateInstanceFromVirtualPath(
            _virtualPath, typeof(Page)) as IDefaultHttpHandler;

        HttpContext.Current.Items["Category"] = _category;

        return handler;
   }
} 

Then you can use:

table.Add(new Route(c.ShortName, new CategoryRouteHandler("~/Lister.aspx", c.ID), ));

And from the code of Lister you can access HttpContext.Current.Items["Category"]

Edit: updated to fix the code, sorry I didn’t test it the first time.