Call UrlHelper in models in ASP.NET MVC

I like Omar's answer but that's not working for me. Just for the record this is the solution I'm using now:

var httpContext = HttpContext.Current;

if (httpContext == null) {
  var request = new HttpRequest("/", "http://example.com", "");
  var response = new HttpResponse(new StringWriter());
  httpContext = new HttpContext(request, response);
}

var httpContextBase = new HttpContextWrapper(httpContext);
var routeData = new RouteData();
var requestContext = new RequestContext(httpContextBase, routeData);

return new UrlHelper(requestContext);

Helpful tip, in any ASP.NET application, you can get a reference of the current HttpContext

HttpContext.Current

which is derived from System.Web. Therefore, the following will work anywhere in an ASP.NET MVC application:

UrlHelper url = new UrlHelper(HttpContext.Current.Request.RequestContext);
url.Action("ContactUs"); // Will output the proper link according to routing info

Example:

public class MyModel
{
    public int ID { get; private set; }
    public string Link
    {
        get
        {
            UrlHelper url = new UrlHelper(HttpContext.Current.Request.RequestContext);
            return url.Action("ViewAction", "MyModelController", new { id = this.ID });
        }
    }

    public MyModel(int id)
    {
        this.ID = id;
    }
}

Calling the Link property on a created MyModel object will return the valid Url to view the Model based on the routing in Global.asax