Routing

MVC gives you great control over how URLs are mapped to your controllers. It gives you the ability to define your URLs in a human readable SEO (Search Engine Optimization) friendly fashion, to remap old URLs to new functionality and side-by-side utilize classic ASP.NET sites inside of MVC3. It also results in hiding what kind of page user is calling and what environment we are working in. Most of the new websites are following this and it is important to understand that routing is not URL rewriting as routing will have customization's and many attachments towards request/response.

When we create any type of MVC application by default GLOBAL.ASAX file is created becoz ASP.NET implements MVC using this global application class mainly. Routes defined in the Global.asax.cs file of our MVC3 web application/site. In this global.asax file most important element relative to our work is RegisterRoutes method. By default, there is only one route defined in the RegisterRoutes method that looks like the line below.

Custom MVC Routes

 In a ASP.NET site for a magazine, you might have a URL that looks like www.internet.com/ViewArticle.aspx?id=123. This URL passes the ID number of the article to view, but the URL itself doesn't describe the content in any human readable way

 If the URL instead was www.internet.com/MVC_Routing/123 a human-or a web crawler-could read that and know that the article is about MVC_ Routing

Defination of Routing :

It is a program or process which is responsible to map the given URL to a controller and its action method.

Explanation: Is the process where user will type the URL which will be converted to handlers and there will be the mediator who will take this Uri and map to the server.

Ex: http://site.com?Productid-123

Now product ID for what(tv,mobile,etc)

In mvc we can define as

http://site.com/show/laptops

Initially routing was provided in MVC today available in entire .Net.

This was introduced because of the way ASP.NET MVC works rather, than being handled by a page handler each request needs to be routed to a specific action method of a specific controller Class.

Routing provides "clean" URLs

URL is mapped to a route handler

Extra level of indirection

Handlers can be changed without impacting URL

URL can be changed without impacting handler

URL Example Example http://www.mysite.com/Home/ProductList 

Note

Catch-all route

Put this route last

It will match any URL which has not matched any other route

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