Static class, java static class
C # The Compiler imposes the following limitations on static classes: 1. Static classes must be derived directly from the base class System. Obect. It does not make sense to derive from any other base classes. Inheritance only applies to objects, but you cannot create instance 2 of static classes. Static classes cannot implement any interfaces. This is because interface method 3 is called only when an instance of applicable classes is used, static classes can only define static members (fields, methods, attributes, and events). Any instance Member will cause the compiler to report errors. 4. Static classes cannot be used as fields, method parameters, or local variables, because they all refer to the variables of the instance, which is not allowed at this time, the compiler will report an error when detecting any such usage.