C# 简单的索引器程序

妖狐艹你老母 2022-01-14 05:43 205阅读 0赞

每次看c\# 时 看到索引器那块就停下来了，看不太懂，也没感到什么实用的地，

正所谓无知啊，今天学习了个简单 索引器

主程序代码：

static void Main(string[] args)
            {
                ProgramGroup group = new ProgramGroup(); //实例化对象
                //Player[] name =new Player[2];//创建演员数组
                创建演员对象并给属性赋值
                //name[0]=new Player(); 
                //name[0].Name="甄子丹";
                //name[0].Role="叶问";
                创建演员对象并给属性赋值
                //name[1]=new Player();
                //name[1].Name="熊黛林";
                //name[1].Role="叶太太";
                //group.Players = name; //把数组赋值给对象的属性
                Console.WriteLine("演员阵容:");
                //for (int i = 0; i < group.Players.Length; i++)
                //{
                //    Console.WriteLine(group.Players[i].Name);//通过属性读取数组的值
                //}
                //group[0] = new Player();
                //group[0].Name = "甄子丹";
                //group[0].Role = "叶问";
                //group[1] = new Player();
                //group[1].Name = "熊黛林";
                //group[1].Role = "叶太太";
                //for (int i = 0; i < 2; i++)
                //{
                //    Console.WriteLine(group[i].Name);
                //}
                group.SetPlayers(); //调用对象的方法给字段赋值
                Console.WriteLine("甄子丹扮演" + group["甄子丹"].Role);
                Console.WriteLine("熊黛林扮演" + group["熊黛林"].Role);
                Console.ReadLine();
               
            }

剧组类代码

class ProgramGroup //剧组类
        {
            //private Player[] players;  //演员数组字段
    
            //public Player[] Players  //演员数组属性
            //{
            //    get { return player; }
            //    set { player = value; }
            //}
            private Player[] players = new Player[2]; //演员数组字段
            //public Player this[int index]  //索引器，index是数组索引
            //{
            //    get { return players[index]; }
            //    set { players[index]=value;}
            //}
            public Player this[string name] //通过演员名称查找的索引器
            {
                get
                {
                    int i = 0;
                    for (; i < 2; i++) //循环查找演员
                    {
                        if (players[i].Name == name)
                        {
                            break;
                        }
                    }
                    if (i == 2)
                    {
                        return null; //没有找到返回空
                    }
                    else
                    {
                        return players[i]; //找到返回数组中的演员元素
                    }
                }
            }
            public void SetPlayers() //给数组赋值
            {
                players[0] = new Player();
                players[0].Name = "甄子丹";
                players[0].Role = "叶问";
                players[1] = new Player();
                players[1].Name = "熊黛林";
                players[1].Role = "叶太太";
            }
        }
        class Player //演员类
        {
            private string name; //演员名称字段
    
            public string Name  //演员名称属性
            {
                get { return name; }
                set { name = value; }
            }
            private string role;  //扮演角色字段
    
            public string Role  //扮演角色属性
            {
                get { return role; }
                set { role = value; }
            }
        }

感觉上面程序还是对索引器不太明白看下一个试试：

班级类：

class Squad //班级类
        {
            string name; //班级名称
    
            public string Name
            {
                get { return name; }
                set { name = value; }
            }
            int count; //学生数量
    
            public int Count
            {
                get { return count; }
                set { count = value; }
            }
        }

年纪类：

class Grade //年级类
        {
            string name; //年级名称
    
            public string Name
            {
                get { return name; }
                set { name = value; }
            }
            Squad[] squads = new Squad[2]; //班级数组
            public Squad this[int index]
            {
                set { squads[index] = value; }
                get { return squads[index]; }
            }
        }

主程序：

class Program
        {
            static void Main(string[] args)
            {
                Grade grade = new Grade(); //实例化对象
                grade.Name = "S1";
                grade[0] = new Squad(); //实例化数组元素对象
                grade[0].Name = "S1T100"; //调用索引器赋值
                grade[0].Count = 25;
                grade[1] = new Squad();
                grade[1].Name = "S1T101";
                grade[1].Count = 29;
                Console.WriteLine(grade.Name+"的班级有");
                Console.WriteLine(grade[0].Name+"里有"+grade[0].Count+"人");
                Console.WriteLine(grade[1].Name + "里有" + grade[1].Count + "人");
                Console.ReadLine();
            }
        }