ASP.NET Routing - capture entire url with constraint

Question

I want to set up a route that will match on any url , with a constraint. This is what I have tried:

routes.MapRouteLowercase("CatchAll Content Validation", "{*url}",
    new { controller = "Content", action = "LoadContent" },
    new { url = new ContentURLConstraint(), }
);

and for testing purposes I have the following simple constraint:

public class ContentURLConstraint : IRouteConstraint
{
    public bool Match(HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values, RouteDirection routeDirection)
    {
        var s = (string)values["url"];
        return s.Contains("comm");              
    }
}

If the constraint is satisfied I when expect to pass the full url to the controll action LoadContent

public ActionResult LoadContent(string url)
{
   return Content(url);
}

I am expecting, when I load a page, for s in the Match function to contain the entire url , so that I can check it, but instead it is null . What might I be missing?

Answer 1

You get null when there is no url in the route, ie host itself: http://localhost:64222 .

When there is a url, eg: http://localhost:64222/one/two , your url parameter will hold a value: one/two .

You can modify your constraint to something like:

public class ContentURLConstraint : IRouteConstraint
{
    public bool Match(HttpContextBase httpContext, Route route, string parameterName, RouteValueDictionary values routeDirection)
    {
        var url = values[parameterName] as string;
        if (!string.IsNullOrEmpty(url))
        {
            return url.Contains("comm");
        }

        return false; // or true, depending on what you need.
    }
}

What might I be missing?

Could be that you are missing that url constraint does not contain host, port, schema and query string. If you need it - you can get it from httpContext.Request .