How to instaniate

How to pass a dto to a base service class (sorry the heading wasn't fully filled out)How to instantiate a base class when calling a regular class. I have a BaseService that I want all of my Service classes to inherits. I want to pass a dto to the base service class that holds some app key settings from the database. How can I call that base service from the UI layer? TestService test = new TestService();  how do I Pass the DTO to the Base Service Class? TestService Class will inherits BaseService().