Question

我刚开始学习C＃。我看到一个老问题，有人试图制作可口可乐机器，这似乎是一个很好的练习。

但我被困在金钱按钮上。我无法弄清楚如何存储按钮在变量中表示的金额，可通过ColaMachine方法访问。

我有以下代码：

using System;
using System.Windows.Forms;
using System.Drawing;

namespace QuickSharp
{
    public class ColaMachine : Form
    {
        public ColaMachine()
        {
            this.Text = "Cola Machine";
            this.Size = new Size(450 , 500);

            //Money & Money Buttons   

            Label Money;
            Money = new Label();
            Money.Text = "Insert Coins Here:";
            Money.Location = new Point(20, 100);
            this.Controls.Add(Money);

            Button MoneyButton1;
            MoneyButton1 = new Button();
            MoneyButton1.Text = "€0,05";
            MoneyButton1.Location = new Point(28,125);
            MoneyButton1.Click += new System.EventHandler(this.MoneyButton1_Click);
            this.Controls.Add(MoneyButton1);

            Button MoneyButton2;
            MoneyButton2 = new Button();
            MoneyButton2.Text = "€0,10";
            MoneyButton2.Location = new Point(28,165);
            MoneyButton2.Click += new System.EventHandler(this.MoneyButton2_Click);
            this.Controls.Add(MoneyButton2);

            Button MoneyButton3;
            MoneyButton3 = new Button();
            MoneyButton3.Text = "€0,20";
            MoneyButton3.Location = new Point(28,205);
            MoneyButton3.Click += new System.EventHandler(this.MoneyButton3_Click);
            this.Controls.Add(MoneyButton3);

            Button MoneyButton4;
            MoneyButton4 = new Button();
            MoneyButton4.Text = "€0,50";
            MoneyButton4.Location = new Point(28,245);
            MoneyButton4.Click += new System.EventHandler(this.MoneyButton4_Click);
            this.Controls.Add(MoneyButton4);

            Button MoneyButton5;
            MoneyButton5 = new Button();
            MoneyButton5.Text = "€1,00";
            MoneyButton5.Location = new Point(28,285);
            MoneyButton5.Click += new System.EventHandler(this.MoneyButton5_Click);
            this.Controls.Add(MoneyButton5);

            Button MoneyButton6;
            MoneyButton6 = new Button();
            MoneyButton6.Text = "€2,00";
            MoneyButton6.Location = new Point(28,325);
            MoneyButton6.Click += new System.EventHandler(this.MoneyButton6_Click);
            this.Controls.Add(MoneyButton6);

            // Drinks & Drink Buttons

            Label Drinks;
            Drinks = new Label();
            Drinks.Text = "Choose Your Drink:";
            Drinks.Location = new Point(315 , 100);
            Drinks.AutoSize = true;
            this.Controls.Add(Drinks);

            Button DrinkButton1;
            DrinkButton1 = new Button();
            DrinkButton1.Text = "Coca-Cola";
            DrinkButton1.Location = new Point(328,125);
            this.Controls.Add(DrinkButton1);

                        Button DrinkButton2;
            DrinkButton2 = new Button();
            DrinkButton2.Text = "Coca-Cola Light";
            DrinkButton2.Location = new Point(328,165);
            this.Controls.Add(DrinkButton2);

                        Button DrinkButton3;
            DrinkButton3 = new Button();
            DrinkButton3.Text = "Fanta";
            DrinkButton3.Location = new Point(328,205);
            this.Controls.Add(DrinkButton3);

                        Button DrinkButton4;
            DrinkButton4 = new Button();
            DrinkButton4.Text = "Sprite";
            DrinkButton4.Location = new Point(328,245);
            this.Controls.Add(DrinkButton4);

                        Button DrinkButton5;
            DrinkButton5 = new Button();
            DrinkButton5.Text = "Spa Blauw";
            DrinkButton5.Location = new Point(328,285);
            this.Controls.Add(DrinkButton5);

                        Button DrinkButton6;
            DrinkButton6 = new Button();
            DrinkButton6.Text = "Red Bull";
            DrinkButton6.Location = new Point(328,325);
            this.Controls.Add(DrinkButton6);

            //Header & Machine Display

            Label Header;
            Header = new Label();
            Header.Text = "Coca-Cola Machine";
            Header.Font = new Font("Arial" , Header.Font.Size +5);
            Header.ForeColor = Color.DarkRed;
            Header.Location = new Point(132, 20);
            Header.AutoSize = true;
            this.Controls.Add(Header);



            TextBox TextBox1 ;
            TextBox1 = new TextBox();

            if(InsertedCoins == 0.00)
                TextBox1.Text = "Buy Your Ice Cold Drinks Here!";
            else
                TextBox1.Text = "Inserted Coins: €" + InsertedCoins;

            TextBox1.BackColor = Color.Black;
            TextBox1.ForeColor = Color.Red;
            TextBox1.Font = new Font("Arial" , TextBox1.Font.Size +3);
            TextBox1.ReadOnly = true;
            TextBox1.Size = new Size(210,300);
            TextBox1.Location = new Point(112,50);

            // I tried to get the text scrolling here... :)
            TextBox1.SelectionStart = TextBox1.Text.Length;
            TextBox1.ScrollToCaret();
            TextBox1.Refresh();

            this.Controls.Add(TextBox1);
        }


        public double InsertedCoins;

        // Money Button Click Events

        private void MoneyButton1_Click(object sender, EventArgs e)
        {
            InsertedCoins = InsertedCoins + 0.05;
        }

        private void MoneyButton2_Click(object sender, EventArgs e)
        {
            InsertedCoins = InsertedCoins + 0.10;
        }

        private void MoneyButton3_Click(object sender, EventArgs e)
        {
            InsertedCoins = InsertedCoins + 0.20;
        }

        private void MoneyButton4_Click(object sender, EventArgs e)
        {
            InsertedCoins = InsertedCoins + 0.50;
        }

        private void MoneyButton5_Click(object sender, EventArgs e)
        {
            InsertedCoins = InsertedCoins + 1.00;
        }

        private void MoneyButton6_Click(object sender, EventArgs e)
        {
            InsertedCoins = InsertedCoins + 2.00;
        }

        private static void Main()
        {

            ColaMachine Scherm;
            Scherm = new ColaMachine();
            Application.Run(Scherm);
        }
    }
}

另外，如果您对我的常规编程有任何提示（例如，为了让其他人尝试阅读我的代码更容易理解），请告诉我！

Answer 1

您可以存储每个按钮i按钮标签属性的金额，并使用事件处理程序中的以下代码来读取金额：

void ValueButton_Click(object sender, EventArgs e)
{
  Button button = sender as Button;
  if (button == null) return;
  if (button.Tag == null) return;
  double amount = (double)button.Tag;

  // Process the amount here....
  InsertedCoins += amount; 
}

Answer 2

首先想到：您应该将问题划分为两个类（类Test和类ColaMachine）。

看起来像：

public class ColaMachine : Form
{
  public ColaMachine()
  {  
     ...
  }
}

public class Test 
{
   private static void Main()
   {
      ColaMachine Scherm;
      Scherm = new ColaMachine();
      Application.Run(Scherm);
   }
}

下一个：如果您想要返回私有的变量，请使用属性。 IC将是一种公共方法（属性）。 InsertedCoins将是一个私有变量。

public double IC
{
   get
   {
      return InsertedCoins;
    }
   set
   {
      InsertedCoins = value;
   }
}

不要忘记，该机器有很多状态。您应该使用设计模式，完全是状态模式。

如何从Button Click事件中获取返回值？

2 个答案: