private static void Main(string[] args) { Employee test = new Employee(); test.EmpInfo(); Console.WriteLine("------------------------"); DervEmployee objDervEmployee = new DervEmployee(); objDervEmployee.EmpInfo(); Console.WriteLine("------------------------"); //注意:objDervEmployee派生类的实例是赋给Employee类的objEmployee的引用, // 所以objEmployee引用调用EmpInfo()方法时 还是调用DervEmployee类的方法 Employee objEmployee = objDervEmployee; objEmployee.EmpInfo(); Console.ReadLine(); }