MVC Ecommerce routing - asp.net-mvc-3

Question

I am trying to get my head around routing for MVC4
I want to create a URL structure consisting of BrandName / ProductType / PageNumber
Sometimes it could just have Brand or just product type deppending on how you filter.
e.g.
Store/{BrandName}//{PaginationId} this is unique
Store/{ProductType}/{PaginationId} this is unique
Store/{BrandName}/{ProductType}/{PaginationId}
Store/{ProductType}/BrandName}/{PaginationId}
Any help?
thanks

Answer 1

You must register the following routes:
// 1: Store/ProductType/BrandName/PaginationId
// (all parts must exists in the URL)
routes.MapRoute("ProductType", "Store/{productType}/{brandName}/{paginationId}",
new { controller = "Store", action = "Index" },
new { /* constraints */ });
// 2: Store/BrandName/ProductType/PaginationId
// 3: Store/BrandName/ProductType
// 4: Store/BrandName
// (both productType and paginationId can be missing)
routes.MapRoute("BrandProduct", "Store/{brandName}/{productType}/{paginationId}",
new { controller = "Store", action = "Index",
productType = UrlParameter.Optional,
paginationId = UrlParameter.Optional},
new { /* constraints */ });
// 5: Store/ProductType/PaginationId
// (all parts must exists in the URL)
routes.MapRoute("ProductType", "Store/{productType}/{paginationId}",
new { controller = "Store", action = "Index",
brandName = 0, paginationId = 0},
new { /* constraints */ });
// Action Index should have 3 parameters: brandName, productType and paginationId
// brandName, productType and paginationId should be nullable
// or reference type (class) to accept nulls
When an URL is received, the first route that matches it will handle it. So there must be a way to distinguish the routes. This can be done using constraints. A constraint is a regex which decides if the received value is valid for a parameter.
Suppose that in the first mapping the ProductType must be something starting with "P", you would add this constraint: new {productType="P.*"}:
If the user types this URL: /Store/P22/TheBrand/12, it will be processed by the first route
If the user types this URL: /Store/TheBrand/P22/12, it won't be processed bythe first route because of the constraint, but will be processed by the second one.
You must disambiguate routes 1 & 2, and also routes 3 & 5
If there is no regex that can do that for you, you can modify the routes with some extra chars that allow to disimbiguate them, ie, put P- and B- before product type nad brand name, like this:
// 1:
routes.MapRoute("ProductType", "Store/P-{productType}/B-{brandName}/{paginationId}",
// 2, 3, 4
routes.MapRoute("BrandProduct", "Store/B-{brandName}/P-{productType}/{paginationId}",
Remember that the routes are processed in the same order in which they are registered.
EDIT - Answer to OP comment:
If you just want a behaviour similar to ASP.NET, where a single page uses all the info, then use this mapping:
routes.MapRoute("Store", "Store", new {controller="Store",action="Index"}}
With this mapping, all the extra information will end up in the query string like this:
http://mysite/Store?ProductType=xxx&BrandName=yyy&PaginationId=23
If you don't provide some of the parameters, they will be simply omitted from the query string.
The action would look like this:
Index(string brandName, string prouctType, int? paginationId)
Note that, as all parameters are optional, they must be nullable (reference type like string or nullable value type like int?). So they'll be automatically bound from the query string, or left null if not present.
There is no reason why you must use Routing. You can use routing to get "smart" urls, but you don't need to.

Answer 2

Create a "main" browsing controller, and make BrandName, ProductType and PaginationId be parameters.
Result:
Store/Browse?BrandName=XX&ProductType=YY&PaginationId=ZZ
You can then overlap some URL-Rewriting logic (link to other SO answer) to achieve the required URL structure.
For cases when a parameter would be missing, I suggest setting them to a default value: for example, if you would not have ProductType, you could do this:
Store/Browse?BrandName=XX&ProductType=ALL&PaginationId=ZZ
In short: if it's missing, default its value and make it so you always have values everywhere they can be. Easier to handle and easier to understand too.