A C# generic class, generic struct or generic interface is modeled through a Modeler Class, Data Type or Interface.
To model a C# generic type in a model:
1. In the model, right-click the Model or Package that is to own the generic type, point to New, point to UML, point to Structure, and then click Class, Data Type (for a struct) or Interface.
2. Type the name of the generic type.
3. Open the item's Property Pages, and then click the Options tab.
4. Select the Template check box.
5. In the Formal Template Parameters box, specify the type parameters.
6. Set up its properties and tagged values as appropriate.
For more information about modeling classes, structs and interfaces, click here
When an item uses the generic type, that item must specify the type arguments through the C# Actual Parameters.