模擬一下人見人恨的「抽獎系統」

1.關於本文

本文旨在模擬一種很是坑爹的抽獎形式-不等機率的抽獎（固然，這種抽獎形式在如今已經獲得了很是廣泛的應用）

程序下載地址：http://pan.baidu.com/s/1hETHk

2.抽獎系統抽獎規則

對外的宣傳是：一共有5個抽獎圖標，用鼠標點擊一個圖標視爲抽獎一次，該圖標所對應的獎品會被翻出。抽獎總共有3次機會，第三次抽獎完畢後，亮出全部圖標後面所表明的獎品。

實現的方法是：一共有5個抽獎圖標，用鼠標點擊一個圖標視爲抽獎一次，計算出一個通常獎品。抽獎總共有3次機會，第三次抽獎完畢後，將其他兩個圖標亮出優質獎品對應的圖片。

下面是一張程序運行時的截圖（抽獎抽到的東西爲何老是這麼不堪入目，看下代碼就明白了~~）

3.圖片資源

本程序的資源都是PNG格式的圖片，存儲在Resource.resx中。這些圖片都是從52poke上下載的。在本程序中，A00-A07被認爲是優質獎品，Z00-Z04被認爲是通常獎品。

4.控件描述

下圖爲本程序用的控件描述

5.程序代碼

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

namespace LuckyDraw
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        //抽獎次數統計
        int iTimes = 0;

        //程序初始化
        private void Form1_Load(object sender, EventArgs e)
        {
            //抽獎次數：0次
            iTimes = 0;

            //初始化圖片：精靈球
            pcb00.Image = Properties.Resources.Ball; pcb00.Image.Tag = "Ball";
            pcb01.Image = Properties.Resources.Ball; pcb01.Image.Tag = "Ball";
            pcb02.Image = Properties.Resources.Ball; pcb02.Image.Tag = "Ball";
            pcb03.Image = Properties.Resources.Ball; pcb03.Image.Tag = "Ball";
            pcb04.Image = Properties.Resources.Ball; pcb04.Image.Tag = "Ball";

            pcb00.Click += PictureClick;
            pcb01.Click += PictureClick;
            pcb02.Click += PictureClick;
            pcb03.Click += PictureClick;
            pcb04.Click += PictureClick;
        }

        //單擊「開始抽獎」按鈕
        private void btnStart_Click(object sender, EventArgs e)
        {
            //抽獎次數：0次
            iTimes = 0;

            //從新開始一局，初始化圖片
            pcb00.Image = Properties.Resources.Ball; pcb00.Image.Tag = "Ball";
            pcb01.Image = Properties.Resources.Ball; pcb01.Image.Tag = "Ball";
            pcb02.Image = Properties.Resources.Ball; pcb02.Image.Tag = "Ball";
            pcb03.Image = Properties.Resources.Ball; pcb03.Image.Tag = "Ball";
            pcb04.Image = Properties.Resources.Ball; pcb04.Image.Tag = "Ball";
        }

        //單擊一張圖片
        private void PictureClick(object sender, EventArgs e)
        {
            //若是已經用盡3次機會，則不觸發後面的行爲
            if (iTimes >= 3) return;

            //已經翻出的牌不會再被翻出
            if (((PictureBox)sender).Image.Tag != "Ball" as object) return;

            //翻一張牌
            ((PictureBox)sender).Image = SelectPicture(false);
            //在翻牌位置繪製一個矩形
            Graphics g = Graphics.FromImage(((PictureBox)sender).Image);
            g.DrawLines(Pens.Red, new Point[] { 
                new Point(10, 10), new Point(90, 10), new Point(90, 90),
                new Point(10, 90), new Point(10, 10) });
            g.Save();

            //抽獎滿三次，翻出全部牌
            if (++iTimes == 3)
            {
                if (pcb00.Image.Tag == "Ball" as object) pcb00.Image = SelectPicture(true);
                if (pcb01.Image.Tag == "Ball" as object) pcb01.Image = SelectPicture(true);
                if (pcb02.Image.Tag == "Ball" as object) pcb02.Image = SelectPicture(true);
                if (pcb03.Image.Tag == "Ball" as object) pcb03.Image = SelectPicture(true);
                if (pcb04.Image.Tag == "Ball" as object) pcb04.Image = SelectPicture(true);
                MessageBox.Show("抽到了這麼多隻好精靈，這下真是賺到了！");
            }
        }

        /// <summary>
        /// 隨機數：供函數 SelectPicture 使用
        /// </summary>
        Random rd = new Random(DateTime.Now.Millisecond);

        /// <summary>
        /// 隨機返回一張精靈圖片
        /// </summary>
        /// <param name="isA">true：高級精靈A00-A07 false：低級精靈Z00-Z04</param>
        /// <returns></returns>
        private Image SelectPicture(bool isA)
        {
            Image result;

            if (isA)
            {
                switch (rd.Next(0, 8))
                {
                  case 0: result = Properties.Resources.A00; result.Tag = "A00"; return result;
                  case 1: result = Properties.Resources.A01; result.Tag = "A01"; return result;
                  case 2: result = Properties.Resources.A02; result.Tag = "A02"; return result;
                  case 3: result = Properties.Resources.A03; result.Tag = "A03"; return result;
                  case 4: result = Properties.Resources.A04; result.Tag = "A04"; return result;
                  case 5: result = Properties.Resources.A05; result.Tag = "A05"; return result;
                  case 6: result = Properties.Resources.A06; result.Tag = "A06"; return result;
                  case 7: result = Properties.Resources.A07; result.Tag = "A07"; return result;
                }
            }
            else
            {
                switch (rd.Next(0, 5))
                {
                  case 0: result = Properties.Resources.Z00; result.Tag = "Z00"; return result;
                  case 1: result = Properties.Resources.Z01; result.Tag = "Z01"; return result;
                  case 2: result = Properties.Resources.Z02; result.Tag = "Z02"; return result;
                  case 3: result = Properties.Resources.Z03; result.Tag = "Z03"; return result;
                  case 4: result = Properties.Resources.Z04; result.Tag = "Z04"; return result;
                }
            }

            return null;
        }
    }
}

END