Route data tokens

A route data token, as opposed to a route token or route parameter, is just some arbitrary data that you supply in a routing table entry and is available for use in the route handling pipeline, including the MVC action method. Unlike route tokens, route data tokens can be any kind of object, not just strings. They have absolutely no meaning for MVC, and will just be ignored, but they can be useful, because you can have multiple routes pointing to the same action method, and you may want to use data tokens to find out which route triggered the call.

You can pass a data token as follows:

app.UseEndpoints(endpoints =>
{
    endpoints.MapControllerRoute(
        name: "default",
        pattern: "{controller}/{action}/{id?}",
        defaults: new { controller = "Home", action = "Index" },
        constraints: null,
        dataTokens: new { foo = "bar" });
});

You can also retrieve them from the...