oop中的多对多关系 [英] Many-to-many relationship in oop

问题描述

可以说我们有两个类，团队和 >玩家

• 任何给定的玩家可以在多个团队


• 任何团队可以拥有尽可能多的玩家，

我喜欢调用方法，如

• playerX.getTeamList（） / code>以获取他/她在
中的所有团队的列表

• teamY.getPlayerList（）以获得团队中所有玩家的列表

（或有一些其他方法可以有效地实现）

我可以想到两种做法，但是他们根本不觉得好像是oop pattens。
你能想到任何好的方法，也许是设计图案？

解决方案

球员和球队之间的关系形成 双向图 。
期待评论（和downvotes？）！我是OOD noob。

  class MyPlayer 
 {
 public string Name {get;组; } 
 
 public MyPlayer（string n）
 {
 Name = n; 
} 
} 
 
 class MyTeam 
 {
 public string Name {get;组; } 
 
 public MyTeam（string n）
 {
 Name = n; 
} 
} 
 
 class PlayerTeamPair 
 {
 public MyPlayer Player {get;组; } 
 public MyTeam Team {get;组; } 
 
 public PlayerTeamPair（MyPlayer p，MyTeam t）
 {
 Player = p; 
团队= t; 
} 
} 
 
 class PlayerTeamBipartiteGraph 
 {
 public List&Player PlayerTeamPair>边缘{get;组; } 
 
 public PlayerTeamBipartiteGraph（）
 {
 Edges = new List&Player PlayerTeamPair>（）; 
} 
 
 public void AddPlayerAndTeam（MyPlayer p，MyTeam t）
 {
 Edges.Add（new PlayerTeamPair（p，t））; 
} 
 
 public List< MyTeam> GetTeamList（MyPlayer p）
 {
 var teams = from e in Edges where e.Player == p select e.Team; 
 return teams.ToList< MyTeam>（）; 
} 
 
 public List< MyPlayer> GetPlayerList（MyTeam t）
 {
 var players = from e in edges where e.Team == t select e.Player; 
 return players.ToList< MyPlayer>（）; 
} 
 
} 
 
 
类程序
 {
 static void Main（string [] args）
 {
 var G = new PlayerTeamBipartiteGraph（）; 
 
 MyPlayer a = new MyPlayer（A）; 
 MyPlayer b = new MyPlayer（B）; 
 MyPlayer c = new MyPlayer（C）; 
 MyPlayer d = new MyPlayer（D）; 
 
 MyTeam t1 = new MyTeam（T1）; 
 MyTeam t2 = new MyTeam（T2）; 
 
 G.AddPlayerAndTeam（a，t1）; 
 G.AddPlayerAndTeam（b，t1）; 
 G.AddPlayerAndTeam（c，t1）; 
 G.AddPlayerAndTeam（b，t2） 
 G.AddPlayerAndTeam（d，t2）; 
 
 G.GetTeamList（b）.ForEach（t => Console.Write（{0}，t.Name））; 
 Console.WriteLine（）; 
 G.GetPlayerList（t2）.ForEach（p => Console.Write（{0}，p.Name））; 
 Console.WriteLine（）; 
} 
} 
  

what is best way to model many-to-many relationship?

lets say we have a two classes , Team and Player

• any given Player can be in multiple Team s
• any Team can have as many Player s as they like

I like to call methods like

• playerX.getTeamList() to get the list of all the Team s he/she is in
• teamY.getPlayerList() to get the list of all the Player s in the team

(or have some other way to do this effectively)

I can think of two ways of doing this , but they just don't feels like good oop pattens. can you think of any good ways , perhaps a design patten ?

解决方案

Relationship between players and teams form Bipartite Graph. Expecting comments(and downvotes?)! I am OOD noob.

    class MyPlayer
    {
        public string Name { get; set; }

        public MyPlayer(string n)
        {
            Name = n;
        }
    }

    class MyTeam
    {
        public string Name { get; set; }

        public MyTeam(string n)
        {
            Name = n;
        }
    }

    class PlayerTeamPair
    {
        public MyPlayer Player { get; set; }
        public MyTeam Team { get; set; }

        public PlayerTeamPair(MyPlayer p,MyTeam t)
        {
            Player = p;
            Team  = t;
        }
    }

    class PlayerTeamBipartiteGraph
    {
        public List<PlayerTeamPair> Edges { get; set; }

        public PlayerTeamBipartiteGraph()
        {
            Edges = new List<PlayerTeamPair>();
        }

        public void AddPlayerAndTeam(MyPlayer p, MyTeam t)
        {
            Edges.Add(new PlayerTeamPair(p, t));
        }

        public List<MyTeam> GetTeamList(MyPlayer p)
        {
            var teams = from e in Edges where e.Player == p select e.Team;
            return teams.ToList<MyTeam>();
        }

        public List<MyPlayer> GetPlayerList(MyTeam t)
        {
            var players = from e in Edges where e.Team == t select e.Player;
            return players.ToList<MyPlayer>();
        }

    }


    class Program
    {
        static void Main(string[] args)
        {
            var G = new PlayerTeamBipartiteGraph();

            MyPlayer a = new MyPlayer("A");
            MyPlayer b = new MyPlayer("B");
            MyPlayer c = new MyPlayer("C");
            MyPlayer d = new MyPlayer("D");

            MyTeam t1 = new MyTeam("T1");
            MyTeam t2 = new MyTeam("T2");

            G.AddPlayerAndTeam(a, t1);
            G.AddPlayerAndTeam(b, t1);
            G.AddPlayerAndTeam(c, t1);
            G.AddPlayerAndTeam(b, t2);
            G.AddPlayerAndTeam(d, t2);

            G.GetTeamList(b).ForEach(t => Console.Write(" {0} ",t.Name));
            Console.WriteLine();
            G.GetPlayerList(t2).ForEach(p => Console.Write(" {0} ",p.Name));
            Console.WriteLine();
        }
    }

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