private static Type GetControllerTypeFromDirectRoute(RouteData routeData)
{
Contract.Assert(routeData != null);
var matchingRouteDatas = routeData.GetDirectRouteMatches();
List<Type> controllerTypes = new List<Type>();
foreach (var directRouteData in matchingRouteDatas)
{
if (directRouteData != null)
{
Type controllerType = directRouteData.GetTargetControllerType();
if (controllerType == null)
{
// We don't expect this to happen, but it could happen if some code messes with the
// route data tokens and removes the key we're looking for.
throw new InvalidOperationException(MvcResources.DirectRoute_MissingControllerType);
}
if (!controllerTypes.Contains(controllerType))
{
controllerTypes.Add(controllerType);
}
}
}
// We only want to handle the case where all matched direct routes refer to the same controller.
// Handling the multiple-controllers case would put attribute routing down a totally different
// path than traditional routing.
if (controllerTypes.Count == 0)
{
return null;
}
else if (controllerTypes.Count == 1)
{
return controllerTypes[0];
}
else
{
throw CreateDirectRouteAmbiguousControllerException(controllerTypes);
}
}