public void TestAddAndCount()
{
_collection = new AttributeCollection();
// Test adding separate attributes
_collection.Add(_a1.Type, _a1);
_collection.Add(_a2);
Assert.AreEqual(2, _collection.Count());
// Test that you cannot add the same attributes more than once
_collection.Add(_a1.Type, _a1);
_collection.Add(_a2.Type, _a2);
Assert.AreEqual(2, _collection.Count());
}