c# - Head First C# Lab1 A Day at the Races 调用的方法未执行

Question

我创建的 greyhound 应用程序有问题。当我使用单选按钮选择谁在下注时(比如 Bob)并将他的赌注金额设置为 10 号狗 4，(见图 #1)当我单击“投注”时，更新“Bob 没有下任何赌注”用 description() 方法标记我得到一个错误(见图 #2)

应该发生的是它说“鲍勃没有下任何赌注”，现在应该是“鲍勃在狗 #4 上赌了 10 美元。我已经确定这是失败的，因为投注者返回 NULL，但我不知道为什么这是 Bettor 引用包含投注者姓名的 Guy 类的时候。

旁注，当比赛结束并且 Bob 获胜时，他会收到报酬，因此 PayOut() 或 Collect() 方法也不起作用。

下面是我的 3 个类和我的 Form1.cs

Greyhound.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Drawing;
using System.Windows.Forms;

namespace A_Day_at_the_Races
{
    public class Greyhound
    {
        public int StartingPosition; //Where my PictureBox starts
        public int RacetrackLength; // How long the racetrack is
        public PictureBox MyPictureBox = null; //My PictureBox object
        public int Location = 0; // My Location on the racetrack
        public Random Randomizer; // An instance of Random

        public bool Run()
        {
            //1. Move forward either 1,2,3 or 4 spaces at random
            int moveforward = Randomizer.Next(1, 4); // declare an int called 'moveforward' will move forward 1,2,3 or 4 spaces at random

            //2. Update the position of my PictureBox on the form
            Point p = MyPictureBox.Location; // current location of the picture of the greyhound
            p.X += moveforward;
            MyPictureBox.Location = p;

            //3. Return true if I won the race
            if (p.X >= RacetrackLength)
                return true;
            else
                return false;
        }

        public void TakeStartingPosition()
        {
            //Reset my location to the start line
            //MyPictureBox.Location.X = StartingPosition;

            StartingPosition = 0;
        }
    }
}

Guy.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace A_Day_at_the_Races
{
    public class Guy
    {
        public string Name; // The guy's name
        public Bet MyBet = null; // An instance of bet() that has how much he's betting
        public int Cash; // How much cash he has
        // these last two fields are the guy's GUI controls on the form
        public RadioButton MyRadioButton; // My RadioButton
        public Label MyLabel; // My Label

        public void UpdateLabels()
        {
            //1.Set my label to my bet's description, 
            if (MyBet == null)
                MyLabel.Text = Name + " hasnt placed any bets";
            else
                MyLabel.Text = MyBet.GetDescription();

            //2.Set the label on my radio button to show my cash ("Joe has 43 dollars")
            MyRadioButton.Text = Name + " has " + Cash + " bucks";
        }

        public void ClearBet()
        {
            //1.Reset my bet so it's zero
            MyBet = null;
        }

        //1.Place a new bet and store it in my bet field
        //2.Return true if the guy had enough money to bet
        public bool PlaceBet(int Amount, int Dog)
        {
            this.MyBet = new Bet();

            if (Cash >= Amount)
            {
                Cash = Cash - Amount;
                MyLabel = new Label();
                MyBet.Amount = Amount;
                MyBet.Dog = Dog;
                UpdateLabels();
                return true;
            }
            else
            {
                return false;
            }
        }

        public void Collect(int Winner)
        {
            if (MyBet != null)
                //1.Ask my bet to pay out (hint use the bet object to do the work)
                Cash += MyBet.PayOut(Winner);
        }
    }
}

Bet.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace A_Day_at_the_Races
{
    public class Bet
    {
         public int Amount; // The amount of cash that was bet
         public int Dog; // The number of the dog the bet is on
         public Guy Bettor; // The guy who placed the bet

         public string GetDescription()
         {
             if (Amount > 0)
                 return Bettor.Name + " bets " + Amount + " bucks on dog #" + Dog;
             else
                 return Bettor.Name + " hasnt placed a bet";
         }

         public int PayOut(int Winner)
         {
             if (Winner == Dog)
                 return Amount;
             else
                 return -1 * Amount;
         }
    }
}

Form1.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace A_Day_at_the_Races
{
    public partial class Form1 : Form
    {
        Guy[] Bettors;
        Greyhound[] Dogs;
        Guy CurrentBettor;

        public Form1()
        {
            InitializeComponent();
            Random Randomizer = new Random();

            //initialise all my guys and dogs
            Bettors = new Guy[3];
            Dogs = new Greyhound[4];

            //guys
            Bettors[0] = new Guy();
            Bettors[0].Name = "Joe";
            Bettors[0].MyRadioButton = joeRadioButton;
            Bettors[0].MyLabel = joeBetLabel;
            Bettors[0].Cash = 50;
            Bettors[0].UpdateLabels();

            Bettors[1] = new Guy();
            Bettors[1].Name = "Bob";
            Bettors[1].MyRadioButton = bobRadioButton;
            Bettors[1].MyLabel = bobBetLabel;
            Bettors[1].Cash = 75;
            Bettors[1].UpdateLabels();

            Bettors[2] = new Guy();
            Bettors[2].Name = "Al";
            Bettors[2].MyRadioButton = alRadioButton;
            Bettors[2].MyLabel = alBetLabel;
            Bettors[2].Cash = 45;
            Bettors[2].UpdateLabels();


            int StartPosition = pictureBoxDog1.Location.X;
            int distance = pictureBox1.Width;
            for (int i = 0; i < 4; i++)
            {
                Dogs[i] = new Greyhound();
                Dogs[i].Randomizer = Randomizer;
                Dogs[i].RacetrackLength = distance;
                Dogs[i].Location = Dogs[i].StartingPosition = StartPosition;
            }

            Dogs[0].MyPictureBox = pictureBoxDog1;
            Dogs[1].MyPictureBox = pictureBoxDog2;
            Dogs[2].MyPictureBox = pictureBoxDog3;
            Dogs[3].MyPictureBox = pictureBoxDog4;

            CurrentBettor = Bettors[0];
        }

        private void RaceButton_Click(object sender, EventArgs e)
        {
            int winner = 0;
            int num_winners = 0;

            while (num_winners == 0)
            {
                for (int i = 0; i < Dogs.Length; i++)
                {
                    if (Dogs[i].Run())
                    {
                        num_winners++;
                        winner = i + 1;
                    }
                }
                Application.DoEvents();
                System.Threading.Thread.Sleep(3);
            }

            if (num_winners > 1)
                MessageBox.Show("We have " + num_winners + " winners");
            else
                MessageBox.Show(" Dog #" + winner + "wins!");

            for (int i = 0; i < Dogs.Length; i++)
            {
                Dogs[i].TakeStartingPosition();
            }

            for (int i = 0; i < Bettors.Length; i ++)
            {
                Bettors[i].Collect(winner);
                Bettors[i].ClearBet();
                Bettors[i].UpdateLabels();
            }

            numericUpDownBet.Value = numericUpDownBet.Minimum;
            numericUpDownDog.Value = numericUpDownDog.Minimum;
        }

        private void joeRadioButton_CheckedChanged(object sender, EventArgs e)
        {
            SetBettor(0);
        }

        private void bobRadioButton_CheckedChanged_1(object sender, EventArgs e)
        {
            SetBettor(1);
        }

        private void alRadioButton_CheckedChanged_1(object sender, EventArgs e)
        {
            SetBettor(2);
        }

        private void BetsButton_Click(object sender, EventArgs e)
        {
            CurrentBettor.PlaceBet((int)numericUpDownBet.Value, (int)numericUpDownDog.Value);
            CurrentBettor.UpdateLabels();
        }
        private void SetBettor(int index)
        {
            CurrentBettor = Bettors[index];
            NameLabel.Text = CurrentBettor.Name;
            if (CurrentBettor.MyBet != null)
            {
                numericUpDownBet.Value = CurrentBettor.MyBet.Amount;
                numericUpDownDog.Value = CurrentBettor.MyBet.Dog;
            }
            else
            {
                numericUpDownBet.Value = numericUpDownBet.Minimum;
                numericUpDownDog.Value = 1;
            }
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            minimumBetLabel.Text = "Minimum Bet $5.00";
        }

        private void ResetButton_Click(object sender, EventArgs e)
        {
            pictureBoxDog1.Location = new Point(61,32);
            pictureBoxDog2.Location = new Point(61,84);
            pictureBoxDog3.Location = new Point(61,131);
            pictureBoxDog4.Location = new Point(61,181);
        }
    }
}

Form1.Designer.cs

namespace A_Day_at_the_Races
{
    partial class Form1
    {
        /// <summary>
        /// Required designer variable.
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary>
        /// Clean up any resources being used.
        /// </summary>
        /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region Windows Form Designer generated code

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
        private void InitializeComponent()
        {
            System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(Form1));
            this.pictureBox1 = new System.Windows.Forms.PictureBox();
            this.pictureBoxDog1 = new System.Windows.Forms.PictureBox();
            this.pictureBoxDog2 = new System.Windows.Forms.PictureBox();
            this.pictureBoxDog3 = new System.Windows.Forms.PictureBox();
            this.pictureBoxDog4 = new System.Windows.Forms.PictureBox();
            this.RaceButton = new System.Windows.Forms.Button();
            this.minimumBetLabel = new System.Windows.Forms.Label();
            this.joeRadioButton = new System.Windows.Forms.RadioButton();
            this.bobRadioButton = new System.Windows.Forms.RadioButton();
            this.alRadioButton = new System.Windows.Forms.RadioButton();
            this.BetsLabel = new System.Windows.Forms.Label();
            this.joeBetLabel = new System.Windows.Forms.Label();
            this.bobBetLabel = new System.Windows.Forms.Label();
            this.alBetLabel = new System.Windows.Forms.Label();
            this.NameLabel = new System.Windows.Forms.Label();
            this.BetsButton = new System.Windows.Forms.Button();
            this.numericUpDownBet = new System.Windows.Forms.NumericUpDown();
            this.label1 = new System.Windows.Forms.Label();
            this.numericUpDownDog = new System.Windows.Forms.NumericUpDown();
            this.ResetButton = new System.Windows.Forms.Button();
            ((System.ComponentModel.ISupportInitialize)(this.pictureBox1)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.pictureBoxDog1)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.pictureBoxDog2)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.pictureBoxDog3)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.pictureBoxDog4)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.numericUpDownBet)).BeginInit();
            ((System.ComponentModel.ISupportInitialize)(this.numericUpDownDog)).BeginInit();
            this.SuspendLayout();
            // 
            // pictureBox1
            // 
            this.pictureBox1.Image = ((System.Drawing.Image)(resources.GetObject("pictureBox1.Image")));
            this.pictureBox1.Location = new System.Drawing.Point(12, 12);
            this.pictureBox1.Name = "pictureBox1";
            this.pictureBox1.Size = new System.Drawing.Size(602, 201);
            this.pictureBox1.TabIndex = 0;
            this.pictureBox1.TabStop = false;
            // 
            // pictureBoxDog1
            // 
            this.pictureBoxDog1.Image = ((System.Drawing.Image)(resources.GetObject("pictureBoxDog1.Image")));
            this.pictureBoxDog1.Location = new System.Drawing.Point(22, 21);
            this.pictureBoxDog1.Name = "pictureBoxDog1";
            this.pictureBoxDog1.Size = new System.Drawing.Size(75, 21);
            this.pictureBoxDog1.TabIndex = 1;
            this.pictureBoxDog1.TabStop = false;
            // 
            // pictureBoxDog2
            // 
            this.pictureBoxDog2.Image = ((System.Drawing.Image)(resources.GetObject("pictureBoxDog2.Image")));
            this.pictureBoxDog2.Location = new System.Drawing.Point(22, 70);
            this.pictureBoxDog2.Name = "pictureBoxDog2";
            this.pictureBoxDog2.Size = new System.Drawing.Size(75, 22);
            this.pictureBoxDog2.TabIndex = 2;
            this.pictureBoxDog2.TabStop = false;
            // 
            // pictureBoxDog3
            // 
            this.pictureBoxDog3.Image = ((System.Drawing.Image)(resources.GetObject("pictureBoxDog3.Image")));
            this.pictureBoxDog3.Location = new System.Drawing.Point(22, 120);
            this.pictureBoxDog3.Name = "pictureBoxDog3";
            this.pictureBoxDog3.Size = new System.Drawing.Size(75, 24);
            this.pictureBoxDog3.TabIndex = 3;
            this.pictureBoxDog3.TabStop = false;
            // 
            // pictureBoxDog4
            // 
            this.pictureBoxDog4.Image = ((System.Drawing.Image)(resources.GetObject("pictureBoxDog4.Image")));
            this.pictureBoxDog4.Location = new System.Drawing.Point(22, 170);
            this.pictureBoxDog4.Name = "pictureBoxDog4";
            this.pictureBoxDog4.Size = new System.Drawing.Size(75, 24);
            this.pictureBoxDog4.TabIndex = 4;
            this.pictureBoxDog4.TabStop = false;
            // 
            // RaceButton
            // 
            this.RaceButton.Location = new System.Drawing.Point(468, 269);
            this.RaceButton.Name = "RaceButton";
            this.RaceButton.Size = new System.Drawing.Size(146, 73);
            this.RaceButton.TabIndex = 5;
            this.RaceButton.Text = "Race!";
            this.RaceButton.UseVisualStyleBackColor = true;
            this.RaceButton.Click += new System.EventHandler(this.RaceButton_Click);
            // 
            // minimumBetLabel
            // 
            this.minimumBetLabel.AutoSize = true;
            this.minimumBetLabel.Font = new System.Drawing.Font("Microsoft Sans Serif", 8.25F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
            this.minimumBetLabel.Location = new System.Drawing.Point(9, 241);
            this.minimumBetLabel.Name = "minimumBetLabel";
            this.minimumBetLabel.Size = new System.Drawing.Size(0, 13);
            this.minimumBetLabel.TabIndex = 6;
            // 
            // joeRadioButton
            // 
            this.joeRadioButton.AutoSize = true;
            this.joeRadioButton.Location = new System.Drawing.Point(12, 269);
            this.joeRadioButton.Name = "joeRadioButton";
            this.joeRadioButton.Size = new System.Drawing.Size(85, 17);
            this.joeRadioButton.TabIndex = 7;
            this.joeRadioButton.TabStop = true;
            this.joeRadioButton.Text = "radioButton1";
            this.joeRadioButton.UseVisualStyleBackColor = true;
            this.joeRadioButton.CheckedChanged += new System.EventHandler(this.joeRadioButton_CheckedChanged);
            // 
            // bobRadioButton
            // 
            this.bobRadioButton.AutoSize = true;
            this.bobRadioButton.Location = new System.Drawing.Point(12, 293);
            this.bobRadioButton.Name = "bobRadioButton";
            this.bobRadioButton.Size = new System.Drawing.Size(85, 17);
            this.bobRadioButton.TabIndex = 8;
            this.bobRadioButton.TabStop = true;
            this.bobRadioButton.Text = "radioButton1";
            this.bobRadioButton.UseVisualStyleBackColor = true;
            this.bobRadioButton.CheckedChanged += new System.EventHandler(this.bobRadioButton_CheckedChanged_1);
            // 
            // alRadioButton
            // 
            this.alRadioButton.AutoSize = true;
            this.alRadioButton.Location = new System.Drawing.Point(12, 317);
            this.alRadioButton.Name = "alRadioButton";
            this.alRadioButton.Size = new System.Drawing.Size(85, 17);
            this.alRadioButton.TabIndex = 9;
            this.alRadioButton.TabStop = true;
            this.alRadioButton.Text = "radioButton2";
            this.alRadioButton.UseVisualStyleBackColor = true;
            this.alRadioButton.CheckedChanged += new System.EventHandler(this.alRadioButton_CheckedChanged_1);
            // 
            // BetsLabel
            // 
            this.BetsLabel.AutoSize = true;
            this.BetsLabel.Font = new System.Drawing.Font("Microsoft Sans Serif", 8.25F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((byte)(0)));
            this.BetsLabel.Location = new System.Drawing.Point(164, 241);
            this.BetsLabel.Name = "BetsLabel";
            this.BetsLabel.Size = new System.Drawing.Size(32, 13);
            this.BetsLabel.TabIndex = 10;
            this.BetsLabel.Text = "Bets";
            // 
            // joeBetLabel
            // 
            this.joeBetLabel.AutoSize = true;
            this.joeBetLabel.Location = new System.Drawing.Point(164, 269);
            this.joeBetLabel.Name = "joeBetLabel";
            this.joeBetLabel.Size = new System.Drawing.Size(35, 13);
            this.joeBetLabel.TabIndex = 11;
            this.joeBetLabel.Text = "label1";
            // 
            // bobBetLabel
            // 
            this.bobBetLabel.AutoSize = true;
            this.bobBetLabel.Location = new System.Drawing.Point(164, 293);
            this.bobBetLabel.Name = "bobBetLabel";
            this.bobBetLabel.Size = new System.Drawing.Size(35, 13);
            this.bobBetLabel.TabIndex = 12;
            this.bobBetLabel.Text = "label1";
            // 
            // alBetLabel
            // 
            this.alBetLabel.AutoSize = true;
            this.alBetLabel.Location = new System.Drawing.Point(164, 317);
            this.alBetLabel.Name = "alBetLabel";
            this.alBetLabel.Size = new System.Drawing.Size(35, 13);
            this.alBetLabel.TabIndex = 13;
            this.alBetLabel.Text = "label1";
            // 
            // NameLabel
            // 
            this.NameLabel.AutoSize = true;
            this.NameLabel.Location = new System.Drawing.Point(9, 359);
            this.NameLabel.Name = "NameLabel";
            this.NameLabel.Size = new System.Drawing.Size(0, 13);
            this.NameLabel.TabIndex = 14;
            // 
            // BetsButton
            // 
            this.BetsButton.Location = new System.Drawing.Point(54, 354);
            this.BetsButton.Name = "BetsButton";
            this.BetsButton.Size = new System.Drawing.Size(75, 23);
            this.BetsButton.TabIndex = 15;
            this.BetsButton.Text = "Bets";
            this.BetsButton.UseVisualStyleBackColor = true;
            this.BetsButton.Click += new System.EventHandler(this.BetsButton_Click);
            // 
            // numericUpDownBet
            // 
            this.numericUpDownBet.Location = new System.Drawing.Point(135, 357);
            this.numericUpDownBet.Minimum = new decimal(new int[] {
            5,
            0,
            0,
            0});
            this.numericUpDownBet.Name = "numericUpDownBet";
            this.numericUpDownBet.Size = new System.Drawing.Size(72, 20);
            this.numericUpDownBet.TabIndex = 16;
            this.numericUpDownBet.Value = new decimal(new int[] {
            5,
            0,
            0,
            0});
            // 
            // label1
            // 
            this.label1.AutoSize = true;
            this.label1.Location = new System.Drawing.Point(214, 359);
            this.label1.Name = "label1";
            this.label1.Size = new System.Drawing.Size(113, 13);
            this.label1.TabIndex = 17;
            this.label1.Text = "bucks on dog number ";
            // 
            // numericUpDownDog
            // 
            this.numericUpDownDog.Location = new System.Drawing.Point(334, 356);
            this.numericUpDownDog.Maximum = new decimal(new int[] {
            4,
            0,
            0,
            0});
            this.numericUpDownDog.Minimum = new decimal(new int[] {
            1,
            0,
            0,
            0});
            this.numericUpDownDog.Name = "numericUpDownDog";
            this.numericUpDownDog.Size = new System.Drawing.Size(79, 20);
            this.numericUpDownDog.TabIndex = 18;
            this.numericUpDownDog.Value = new decimal(new int[] {
            1,
            0,
            0,
            0});
            // 
            // ResetButton
            // 
            this.ResetButton.Location = new System.Drawing.Point(468, 349);
            this.ResetButton.Name = "ResetButton";
            this.ResetButton.Size = new System.Drawing.Size(146, 41);
            this.ResetButton.TabIndex = 19;
            this.ResetButton.Text = "Reset";
            this.ResetButton.UseVisualStyleBackColor = true;
            this.ResetButton.Click += new System.EventHandler(this.ResetButton_Click);
            // 
            // Form1
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(626, 410);
            this.Controls.Add(this.ResetButton);
            this.Controls.Add(this.numericUpDownDog);
            this.Controls.Add(this.label1);
            this.Controls.Add(this.numericUpDownBet);
            this.Controls.Add(this.BetsButton);
            this.Controls.Add(this.NameLabel);
            this.Controls.Add(this.alBetLabel);
            this.Controls.Add(this.bobBetLabel);
            this.Controls.Add(this.joeBetLabel);
            this.Controls.Add(this.BetsLabel);
            this.Controls.Add(this.alRadioButton);
            this.Controls.Add(this.bobRadioButton);
            this.Controls.Add(this.joeRadioButton);
            this.Controls.Add(this.minimumBetLabel);
            this.Controls.Add(this.RaceButton);
            this.Controls.Add(this.pictureBoxDog4);
            this.Controls.Add(this.pictureBoxDog3);
            this.Controls.Add(this.pictureBoxDog2);
            this.Controls.Add(this.pictureBoxDog1);
            this.Controls.Add(this.pictureBox1);
            this.Name = "Form1";
            this.Text = "Form1";
            this.Load += new System.EventHandler(this.Form1_Load);
            ((System.ComponentModel.ISupportInitialize)(this.pictureBox1)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.pictureBoxDog1)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.pictureBoxDog2)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.pictureBoxDog3)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.pictureBoxDog4)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.numericUpDownBet)).EndInit();
            ((System.ComponentModel.ISupportInitialize)(this.numericUpDownDog)).EndInit();
            this.ResumeLayout(false);
            this.PerformLayout();

        }

        #endregion

        private System.Windows.Forms.PictureBox pictureBox1;
        private System.Windows.Forms.PictureBox pictureBoxDog1;
        private System.Windows.Forms.PictureBox pictureBoxDog2;
        private System.Windows.Forms.PictureBox pictureBoxDog3;
        private System.Windows.Forms.PictureBox pictureBoxDog4;
        private System.Windows.Forms.Button RaceButton;
        private System.Windows.Forms.Label minimumBetLabel;
        private System.Windows.Forms.RadioButton joeRadioButton;
        private System.Windows.Forms.RadioButton bobRadioButton;
        private System.Windows.Forms.RadioButton alRadioButton;
        private System.Windows.Forms.Label BetsLabel;
        private System.Windows.Forms.Label joeBetLabel;
        private System.Windows.Forms.Label bobBetLabel;
        private System.Windows.Forms.Label alBetLabel;
        private System.Windows.Forms.Label NameLabel;
        private System.Windows.Forms.Button BetsButton;
        private System.Windows.Forms.NumericUpDown numericUpDownBet;
        private System.Windows.Forms.Label label1;
        private System.Windows.Forms.NumericUpDown numericUpDownDog;
        private System.Windows.Forms.Button ResetButton;
    }
}

Answer 1

在 PlaceBet 方法中您忘记设置 Bettor 属性:

            if (Cash >= Amount)
            {
                Cash = Cash - Amount;
                MyLabel = new Label();
                MyBet.Amount = Amount; // HERE
                MyBet.Dog = Dog; // HERE
                UpdateLabels();
                return true;

只需在此处添加一行:

                MyBet.Bettor = this;

解释/基本原理:关键是如果没有它，当“Guy”创建“Bet”时，Bet 不知道是谁创建的。在您的代码中没有任何地方设置 Bettor 字段，因此它永远没有机会设置为有意义的内容。投注将仅保留此字段中的默认 NULL 值。因为我实际上并没有阅读/跟踪所有代码，所以我认为最简单的方法是让 Bet 从一开始就知道他的主人。