概念:

语法:

    class Teacher //父类,基类
    {
        public string name;
        public int number;
        public void SpeakName() 
        {
        }
    }
    class TeachingTeacher : Teacher
    {
        public string sbject; //子类,派生类有自己的成员
        public void SeakSubject() 
        {
        }
    }
        internal class Program
    {
        static void Main(string[] args)
        {
            TeachingTeacher tt = new TeachingTeacher();
            tt.number = 1;
            tt.name = "Leemoon";
        }
    }

只能继承一个父类;

总结: