C#设计模式——（结构型-外观设计模式）

        public class DaTing
        {
            private Police Police=new Police();
            private Street Street = new Street();
            private Hospital Hospital = new Hospital();
            public void KaiZhengMing()
            {
                this.Police.GetHuji();
                this.Street.GetHuKou();
                this.Hospital.GetChusheng();
            }
        }
        public class Police
        {
            public void GetHuji()
            {
                Console.WriteLine("开具户籍证明");
            }
        }
        public class Street
        {
            public void GetHuKou()
            {
                Console.WriteLine("开具户口证明");
            }
        }
        public class Hospital
        {
            public void GetChusheng()
            {
                Console.WriteLine("开具出生证明");
            }
        }

            DaTing daTing = new DaTing();
            daTing.KaiZhengMing();