CSharp: Composite Pattern in donet core 3

/// <summary>
    ///组合模式 Composite Pattern
    /// geovindu,Geovin Du edit
    /// 
    /// </summary>
    interface IEmployee
    {
 
        /// <summary>
        /// To set an employee name
        /// 姓名
        /// </summary>
        string Name { get; set; }

        /// <summary>
        /// To set an employee department
        /// 部门
        /// </summary>
        string Dept { get; set; }
   

        /// <summary>
        /// To set an employee designation
        /// 描述
        /// </summary>
        string Designation { get; set; }
  
        /// <summary>
        /// To display an employee details
        /// 清单详情
        /// </summary>
        void DisplayDetails();

       // string getToString();

    }
    /// <summary>
    /// Leaf Node
    /// </summary>
    class Employee : IEmployee
    {
        /// <summary>
        /// 姓名：
        /// </summary>
        public string Name { get; set; }
        /// <summary>
        /// 部门
        /// </summary>
        public string Dept { get; set; }
        /// <summary>
        /// 描述
        /// </summary>
        public string Designation { get; set; }
        /// <summary>
        /// 详情清单 Details of a leaf node
        /// </summary>
        public void DisplayDetails()
        {
           // Console.WriteLine($"\t姓名：{Name} 工作在 {Dept} 部门.描述:{Designation}");
            Console.WriteLine(getToString());
        }
        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>     
        public string getToString()
        {
            return $"\t姓名：{Name} 工作在 {Dept} 部门.描述:{Designation}";
        }
    }
    /// <summary>
    /// 父类 Non-leaf node
    /// </summary>
    class CompositeEmployee : IEmployee
    {

        /// <summary>
        /// 姓名：
        /// </summary>
        public string Name { get; set; }
        /// <summary>
        /// 部门
        /// </summary>
        public string Dept { get; set; }
        /// <summary>
        /// 描述
        /// </summary>
        public string Designation { get; set; }
        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public string getToString()
        {
            //return $"{nameof(Name)}: {Name}, {nameof(Dept)}: {Dept}, {nameof(Designation)}: {Designation}";
            return $"\t姓名：{Name} 工作在 {Dept} 部门.描述:{Designation}";
        }

        /// <summary>
        /// 子类对象 The container for child objects
        /// </summary>
        private List<IEmployee> subordinateList = new List<IEmployee>();

        /// <summary>
        /// 添加 To add an employee
        /// </summary>
        /// <param name="e"></param>
        public void AddEmployee(IEmployee e)
        {
            subordinateList.Add(e);
        }

        /// <summary>
        /// 移除 To remove an employee
        /// 
        /// </summary>
        /// <param name="e"></param>
        public void RemoveEmployee(IEmployee e)
        {
            subordinateList.Remove(e);
        }

        /// <summary>
        /// 详情清单 Details of a composite node
        /// </summary>
        public void DisplayDetails()
        {

            //getToString();
            //Console.WriteLine($"\n姓名：{Name} 工作在 {Dept} 部门.描述:{Designation}");
            Console.WriteLine(getToString());

            foreach (IEmployee e in subordinateList)
            {
            
                e.DisplayDetails();
            }
        }
    }

　　

 /// <summary>
    ///组合模式 Composite Pattern
    /// geovindu,Geovin Du edit
    /// </summary>
    public class GraphicObject
    {

        /// <summary>
        /// 
        /// </summary>
        public virtual string Name { get; set; } = "组";
        /// <summary>
        /// 
        /// </summary>
        public string Color;
        /// <summary>
        /// 
        /// </summary>
        private readonly Lazy<List<GraphicObject>> children
          = new Lazy<List<GraphicObject>>();
        /// <summary>
        /// 
        /// </summary>
        public List<GraphicObject> Children => children.Value;
        /// <summary>
        /// 
        /// </summary>
        /// <param name="sb"></param>
        /// <param name="depth"></param>
        private void Print(StringBuilder sb, int depth)
        {
            sb.Append(new string('*', depth))
              .Append(string.IsNullOrWhiteSpace(Color) ? string.Empty : $"{Color} ")
              .AppendLine($"{Name}");
            foreach (var child in Children)
                child.Print(sb, depth + 1);
        }
        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public override string ToString()
        {
            var sb = new StringBuilder();
            Print(sb, 0);
            return sb.ToString();
        }
    }
    /// <summary>
    /// 
    /// </summary>
    public class Circle : GraphicObject
    {
        public override string Name => "圆";
    }
    /// <summary>
    /// 
    /// </summary>
    public class Square : GraphicObject
    {
        public override string Name => "正方形";
    }

　　

调用：

 //组合模式
            Console.WriteLine("***组合模式Composite Pattern Demo. ***");

            #region Mathematics department
            //2 lecturers work in Mathematics department
            Employee mathTeacher1 = new Employee { Name = "老大", Dept = "数学", Designation = "讲师" };
            Employee mathTeacher2 = new Employee { Name = "老二", Dept = "数学", Designation = "讲师" };

            //The college has a Head of Department in Mathematics
            CompositeEmployee hodMaths = new CompositeEmployee { Name = "老六", Dept = "数学", Designation = "数学系主任" };

            //Lecturers of Mathematics directly reports to HOD-Maths
            hodMaths.AddEmployee(mathTeacher1);
            hodMaths.AddEmployee(mathTeacher2);
            #endregion

            #region Computer Science department
            //3 lecturers work in Computer Sc. department
            Employee cseTeacher1 = new Employee { Name = "老三", Dept = "计算机科学", Designation = "讲师" };
            Employee cseTeacher2 = new Employee { Name = "老四", Dept = "计算机科学", Designation = "讲师" };
            Employee cseTeacher3 = new Employee { Name = "老五", Dept = "计算机科学", Designation = "讲师" };

            //The college has a Head of Department in Computer science
            CompositeEmployee hodCompSc = new CompositeEmployee { Name = "老幺", Dept = "计算机科学.", Designation = "计算机科学系主任" };

            //Lecturers of Computer Sc. directly reports to HOD-CSE
            hodCompSc.AddEmployee(cseTeacher1);
            hodCompSc.AddEmployee(cseTeacher2);
            hodCompSc.AddEmployee(cseTeacher3);
            #endregion

            #region Top level management
            //The college also has a Principal
            CompositeEmployee principal = new CompositeEmployee { Name = "族长", Dept = "规划监督管理", Designation = "校长" };

            //Head of Departments's of Maths and Computer Science directly reports to Principal.
            principal.AddEmployee(hodMaths);
            principal.AddEmployee(hodCompSc);
            #endregion

            /* 
             * Printing the leaf-nodes and branches in the same way.
             * i.e. in each case, we are calling DisplayDetails() method.
            */
            Console.WriteLine("\nDetails of a Principal(校长) object is as follows:");
            //Prints the complete structure
            principal.DisplayDetails();

            Console.WriteLine("\nDetails of a HOD(系主任） object is as follows:");
            //Prints the details of Computer Science department
            hodCompSc.DisplayDetails();

            //Leaf node
            Console.WriteLine("\nDetails of an individual employee(leaf node一般教职员) is as follows:");
            mathTeacher1.DisplayDetails();

            /*
             * Suppose, one Computer Science lecturer(老幺) 
             * is leaving now from the organization.
             */
            hodCompSc.RemoveEmployee(cseTeacher2);
            Console.WriteLine("\n成员：");
            principal.DisplayDetails();


            var drawing = new GraphicObject { Name = "我的画" };
            drawing.Children.Add(new Square { Color = "红色" });
            drawing.Children.Add(new Circle { Color = "黄色" });

            var group = new GraphicObject();
            group.Children.Add(new Circle { Color = "蓝色" });
            group.Children.Add(new Square { Color = "蓝色" });
            drawing.Children.Add(group);

            Console.WriteLine(drawing);

　　

输出：

***组合模式Composite Pattern Demo. ***

Details of a Principal(校长) object is as follows:

姓名：族长 工作在 规划监督管理 部门.描述:校长

姓名：老六 工作在 数学 部门.描述:数学系主任
        姓名：老大 工作在 数学 部门.描述:讲师
        姓名：老二 工作在 数学 部门.描述:讲师

姓名：老幺 工作在 计算机科学. 部门.描述:计算机科学系主任
        姓名：老三 工作在 计算机科学 部门.描述:讲师
        姓名：老四 工作在 计算机科学 部门.描述:讲师
        姓名：老五 工作在 计算机科学 部门.描述:讲师

Details of a HOD(系主任） object is as follows:

姓名：老幺 工作在 计算机科学. 部门.描述:计算机科学系主任
        姓名：老三 工作在 计算机科学 部门.描述:讲师
        姓名：老四 工作在 计算机科学 部门.描述:讲师
        姓名：老五 工作在 计算机科学 部门.描述:讲师

Details of an individual employee(leaf node一般教职员) is as follows:
        姓名：老大 工作在 软件 部门.描述:讲师

成员：

姓名：族长 工作在 规划监督管理 部门.描述:校长

姓名：老六 工作在 数学 部门.描述:数学系主任
        姓名：老大 工作在 软件 部门.描述:讲师
        姓名：老二 工作在 软件 部门.描述:讲师

姓名：老幺 工作在 计算机科学. 部门.描述:计算机科学系主任
        姓名：老三 工作在 计算机科学 部门.描述:讲师
        姓名：老五 工作在 计算机科学 部门.描述:讲师
我的画
*红色 正方形
*黄色 圆
*组
**蓝色 圆
**蓝色 正方形