C＃繼承父類的屬性

Question

我想讓我的Player對象繼承錦標賽中的籌碼總和。我得到（試圖除以零），我認爲這是因爲它無法從父錦標賽對象繼承芯片。爲什麼這不起作用？

public partial class Form1 : Form 
{ 
    public Tournament Tournament { get; set; } 

    public Form1() 
    { 
     InitializeComponent(); 

     Tournament = new Tournament(); 
     Tournament.PlayerList.Add(new Player("Hero", 5000)); 
     Tournament.PlayerList.Add(new Player("Villain1", 3000)); 
     Tournament.PlayerList.Add(new Player("Villain2", 4000)); 

     MessageBox.Show(Tournament.PlayerList[0].StackPercentage.ToString()); 
    } 
} 

public class Tournament 
{ 
    public List<Player> PlayerList { get; set; } 
    public int Chips 
    { 
     get 
     { 
      return PlayerList.Sum(S => S.Stack); 
     } 
    } 

    public Tournament() 
    { 
     PlayerList = new List<Player>(); 
    } 
} 

public class Player : Tournament 
{ 
    public string ID { get; set; } 
    public int Stack { get; set; } 
    public double StackPercentage 
    { 
     get 
     { 
      return Stack/Chips; 
     } 
    } 

    public Player(string _ID, int _Stack) 
    { 
     ID = _ID; 
     Stack = _Stack; 
    } 
} 

Answer 1

你不應該從錦標賽派生玩家。通過這樣做，你就是說每個球員都是比賽。

嘗試這樣：

public interface IPlayer {} 

public abstract class Player : IPlayer 
{ 
    public ITournament CurrentTournament { get; set; } 
} 

public class PokerPlayer : Player 
{ 
    public PokerPlayer() {} 
    public int CurrentChips { get; set; } 

    public double StackPercentage 
    { 
    get { return this.CurrentChips/(PokerTournament)this.CurrentTournament.StartingChips; } 
    } 
} 

public interface ITournament {} 

public abstract class Tournament : ITournament 
{ 
    public List<Player> Players { get; set; } 
    public int PlayerCount { get { return this.Players.Count; } } 
} 

public class PokerTournament : Tournament 
{ 
    private PokerTournament() {} 
    public PokerTournament(int startingChips) 
    { 
    if(startingChips < 1) throw new ArgumentException("Invalid starting amount.", "startingChips"); 
    this.StartingChips = startingChips; 
    } 

    public int StartingChips { get; set; } 
} 

Answer 2

繼承似乎很好。

我覺得找你的問題是，PlayerList可能是空的或List每Player的芯片等於零，因此總和是零太。

讓StackPercentage考慮到Chips相等的可能性零是否有意義或修復填充PlayerList的邏輯，這樣Chips不能零如初。

編輯：你編輯了你的問題，但你寫的代碼甚至不會編譯......我不確定你的問題是什麼，除非你澄清你的代碼。

試試這個：

public Form1() 
{ 
    .... 
    Tournament tournament = new Tournament(); 
    tournament.PlayerList.Add(new Player("Hero", 5000)); 
    tournament.PlayerList.Add(new Player("Villain1", 3000)); 
    tournament.PlayerList.Add(new Player("Villain2", 4000)); 
    int chips = tournament.PlayerList[0].StackPercentage.ToString(); 
} 

反正這不會工作。詳情請見Haris Hasan's回答。基本上tournament與(Tournament)PlayerList[0]不是同一個對象。請記住，每次創建Player實例時，都會創建一個新的基類實例，其相應的模式爲PlayerList。

你不應該在這裏使用繼承。 A Player和Tournament完全沒有繼承關係。 A Player不是Tournament。擺脫了繼承關係的，只是移動StackPercentage到Tournament類，並將其轉換成需要Player實例作爲參數的方法：

public double StackPercentage(Player player) 
    { 
     return player.Stack/this.Chips; 
    } 

Answer 3

問題在這段代碼是我們假定你是Tournament.PlayerList[0]將指向相同球員列表作爲實例Tournament正在做，但事實並非如此。 PlayerList[0]的PlayerList集合是空的。

public double StackPercentage 
    { 
     get 
     { 
      //Chips here is 0 because the PlayerList of Player instance is empty 
      return Stack/Chips; 
     } 
    } 

Player類擁有它自己的PlayerList。