Avoid IndexOutOfRangeException Indexing DataReader Columns?

I am having a little trouble with an 'IndexOutOfRangeException'. I think it is because when the code tries to get the DateModified col from the database it sometimes contains NULLS (the users haven't always updated the page since they created it).

Here is my code;

s = ("select datemodified, maintainedby, email, hitcount from updates where id = @footid")
Dim x As New SqlCommand(s, c)
x.Parameters.Add("@footid", SqlDbType.Int)
x.Parameters("@footid").Value = footid
c.Open()
Dim r As SqlDataReader = x.ExecuteReader
While r.Read
If r.HasRows Then
datemodified = (r("DateModified"))
maintainedby = (r("maintainedby"))
= (r("email"))
hitcount = (r("hitcount"))
End If
End While
c.Close()


I thought (after a bit of msdn) that adding;

If r.HasRows Then
End If

after adding I am still getting the same old IndexOutOfRangeException

(ps, I have tried datemodified as string / datetime)