Refactoring: Extracting Superclass

To use the "Extract superclass" operation:

Select one or more code elements (class, interface, field, method, event, property, or indexer) in the Diagram or Model View.
On the main menu, choose RefactoringExtract Superclass
Tip: Alternatively, you can choose Refactoring->Extract Superclass
on the context menu of the selection.
In the Extract superclass dialog box, enter the name for the interface and designate its namespace, if applicable.
Specify the members to be used in the resulting superclass by setting or clearing the respective check-boxes. If applicable, indicate that a method is abstract in the extracted superclass.
Click OK. The Refactoring window opens allowing you to review the refactoring before committing to it.
Click the Perform refactoring button to complete the extraction.