Hi,
The class attributes in G# is the same as static fields in C#. The class attributes of a class doesn't belong to a specific object, but is common for the whole class. Therefore there is no reference in or reference out needed when accessing the class attributes. You don't need to create any object of the class in order to use the class attributes. A method that only access class attributes are called class method or static method.
You could actually create a static class, this is a class that only contains class attribute and no object could be created, since there is no constructor. You can't inherit a static class either. This icon overlay symbol will have a different green color as well. In the G# Debugger you could see the class attributes, but notice that they don't change when choosing a different object to monitor, since they are all shared by all the object within the class.
How do you use the class attributes? Well, it is of couse a design issue, but I generaly try to avoid using class attributes as much as possible. Usually it is better to create a new class and create one object that is aggregated by the other objects (of the class that you might want to use class attributes). If I would use class attributes, it could typically be to store a reservation table of keep track of resources.
When do you use a static class? Well, also hard to answer, since it is a design issue. I don't use them very much, but I have used them in situation when there obviously couldn't be objects. One example is when I implemented a web service, I contained all web services as static methods, using the class attributes as storage of certain connection parameters.
Here is one source for further reading of static attributes and classes in C#. I use C# as the "reference" when creating the behaviour in G#.
http://msdn.microsoft.com/en-us/library/79b3xss3.aspx
Thanks,
Mattias
