Host selection from attributes

Starting in ASP.NET 3, it is also possible to restrict a route based on the host header and port. You can either do that through attributes or by using fluent (code-based) configuration.

Here's an example of using attributes:

[Host("localhost", "127.0.0.1")]
public IActionResult Local() { ... }

[Host("localhost:80")]
public IActionResult LocalPort80() { ... }

[Host(":8080")]
public IActionResult Port8080() { ... }

We have three examples of using the [Host] attribute here:

1. The first one makes the Localaction method reachable only if the local header is localhost or 127.0.0.1; any number of host headers can be provided.
2. The second example demands a combination of host header and port, in this case, 80.
3. The final one just expects port 8080.

The [Host] attribute can, of course, be combined with any [Http*] or [Route] ones.

Here...