I have a unit test and am checking for null exceptions of my controller constructor for a few different services.

```
[TestMethod]
[ExpectedException(typeof(ArgumentNullException))]

```

In my controller constructor I have:

```
 if (routeCategoryServices == null)
    throw new ArgumentNullException("routeCategoryServices");

 if (routeProfileDataService == null)
    throw new ArgumentNullException("routeProfileDataService");

```

I have a unit test for each, but how can I distinguish between the two. I can leave the test as is as either of the checks could be throwing null so I want to test the exception by param name. 

Is this possible?