MVC routes.MapRoute name property - asp.net-mvc

Question

I'm brand new to MVC so please bear with me as I'm only on the second page of the MS Tutorial (see last code example). For the HelloWorldController the following MapRoute is added:
routes.MapRoute(
name: "Hello",
url: "{controller}/{action}/{name}/{id}");
I'm just wondering, is it purely the pattern matching that does the work and the name "Hello" is just for my own reference? If so, are there not naming conventions that should be followed saying the MapRoute should be called HelloWorldWelcome, where welcome is a method inside the HelloWorldController.cs (see above link). Or am i being pedantic?

Answer 1

The route name is also used by the UrlHelper class. For example:
var url = Url.Route("Hello", new
{
controller = "SomeController",
action = "SomeAction",
name = "charlie",
id = 123
});
This will generate a matching URL.
This feature is much more useful when you use Attribute Routing. For example, if on some controller you have an action:
[RoutePrefix("api/phonebook")]
public class PhonebookController
{
[HttpGet("contact/{id}", Name = "GetContact")]
public Contact GetContact(int id)
{
...
}
}
In other code you could use Url.Route("GetContact", new { id = 7 }) to generate the URL /api/phonebook/contact/7.

Answer 2

Please refer to details on ASP.NET MVC Routing Overview
Name attribute is for callign a route from your views or controller with route name.
From ActionLink your can use a routename:
Html.RouteLink("link_text", "route_name", route_parameters)

Answer 3

The question seems to be not so clearly answered (how the "Hello" route is choosen by the "HelloWorld" controller?), but as an Asp.Net MV5 begginer, I can see that the route is selected by default according to the match between the router url property and the URL parameters.

Answer 4

routes.MapRoute(
name: "Default",
url: "{controller}/{action}/{id}",
defaults: new { controller = "ImageScan", action = "ScanImage", id = UrlParameter.Optional },
namespaces: new[] { "WebApplication3.Controllers" }
);
I am finding error :
Description: HTTP 404. The resource you are looking for (or one of its dependencies) could have been removed, had its name changed, or is temporarily unavailable. Please review the following URL and make sure that it is spelled correctly.
Requested URL: /Views/ImageScan/ScanImage.cshtml