public partial class PictureControl : UserControl{    public event MouseEventHandler PicControl_DoubleClick;    private int picNum;    /// <summary>    /// 屏幕個數    /// </summary>    public int PicNum    {      get { return picNum; }      set      {        if (value == 4 || value == 6 || value == 9 || value == 12 || value == 16 || value == 20 || value == 25)//只能是4、6、9、12、16、20、25        {          picNum = value;          this.SetPictureBox(this.picNum);        }        else        {          this.PicNum = 12;          this.SetPictureBox(this.picNum);        }      }    }    public PictureControl()    {      this.picNum = 4;      InitializeComponent();      this.SetPictureBox(this.picNum);    }    /// <summary>    /// 根據個數布局PictureBox    /// </summary>    /// <param name="num"></param>    private void SetPictureBox(int num)    {      this.Controls.Clear();      Size size = this.Size;      switch (num)      {        case 4: this.SetPictureBox(2, 2, size); break;        case 6: this.SetPictureBox(2, 3, size); break;        case 9: this.SetPictureBox(3, 3, size); break;        case 12: this.SetPictureBox(3, 4, size); break;        case 16: this.SetPictureBox(4, 4, size); break;        case 20: this.SetPictureBox(4, 5, size); break;        case 25: this.SetPictureBox(5, 5, size); break;      }    }    /// <summary>    /// 布局pictureBox    /// </summary>    /// <param name="x">幾行</param>    /// <param name="y">幾列</param>    /// <param name="size">當前控件的大小</param>    private void SetPictureBox(int x, int y,Size size)    {      int num = 0;      for (int i = 0; i < x; i++)      {        for (int j = 0; j < y; j++)        {          PictureBox pic = new PictureBox();          pic.SizeMode = PictureBoxSizeMode.Zoom;                     //設置自動縮放          pic.BackColor = Color.White;                          //設置背景顏色          pic.Location = new Point((size.Width / y) * j, (size.Height / x) * i);     //設置Location          pic.BorderStyle = BorderStyle.FixedSingle;                   //設置邊框          pic.MouseDoubleClick += new MouseEventHandler(pic_MouseDoubleClick);      //訂閱控件雙擊事件          pic.Size = new Size(size.Width / y, size.Height / x);              //設置控件大小             pic.Tag = num;                                 //設定控件編號即屏幕序號          this.Controls.Add(pic);                             //添加          num++;        }      }    }    void pic_MouseDoubleClick(object sender, MouseEventArgs e)    {      if (this.PicControl_DoubleClick != null)      {        this.PicControl_DoubleClick(sender, e);//將動態添加的控件的雙擊事件 傳向控件體外。      }    }    private void PictureControl_SizeChanged(object sender, EventArgs e)    {      this.SetPictureBox(this.picNum);    }    private PictureBox GetPicByIndex(int index)    {      foreach (Control c in this.Controls)      {        if (Convert.ToInt32(c.Tag) == index)        {          return (PictureBox)c;        }      }      PictureBox p = new PictureBox();      p.Tag = -1;      return p;    }    /// <summary>    /// 根據屏幕序號設置圖像    /// </summary>    /// <param name="index">屏幕號</param>    /// <param name="img">圖像</param>    public void SetImageByIndex(int index, Image img)    {      GetPicByIndex(index).Image = img;    }}