ASP. NET learning notes (14)-abstract class and interface

I. abstract classes
1. abstract classes do not have to have abstract attributes and abstract methods. abstract classes must be declared after the abstract methods are declared;
2. The subclass must be an abstract method of the override base class;

2. API www.2cto.com
1. Only methods can be included;
2. The interface cannot contain constants, fields, constructors, destructor, or static members;
3. All members in the interface are set to public by default;
4. Subclass must implement all the members in the interface;
5. A class can implement multiple interfaces separated by commas;
6. An interface can have multiple interfaces. All members of the parent interface must be implemented;

Iii. Differences between abstract classes and interfaces
1. abstract classes are incomplete classes and need to be further refined; interfaces are just a specification or provision of behavior;
2. The method of the abstract class is virtual by default, and the method in the interface is non-virtual by default. It can also be declared as virtual;
By: dxh_0829