C#更改多个控件的背景图片

Question

在 C# 表单中，我创建了一个函数，该函数一旦被调用，就会创建一个具有所需图像、大小和位置的图片框：

private void NewPic(string nName, int locX, int locY, int SizX, int SizY, Image Img)
{
    PictureBox Pic = new PictureBox();
    Pic.Name = nName; Pic.Image = Img;
    Pic.BackColor = Color.Transparent;
    Pic.SizeMode = System.Windows.Forms.PictureBoxSizeMode.StretchImage;
    Pic.Size = new System.Drawing.Size(SizX, SizY);
    Pic.Location = new System.Drawing.Point(locX, locY);
    Controls.Add(Pic);
    Pic.Click += new EventHandler(Pic_Click);
}

现在当我需要一张图片时，我会这样做：

NewPic("FIRE", 32, 100, 120, 120, Properties.Resources.Image);

问题是，在点击事件中，当我点击图片框时，我希望它更改其背景图片，但是，如果我点击其他图片框，我希望最后一个图片框自行重置：

private void Pic_Click(object sender, System.EventArgs e)
{
    PictureBox pb = (PictureBox)sender;
    switch (pb.Name)
    {
        case "1": 
            pb.BackgroundImage = Properties.Resources.OtherImg; //creates the background
            pb.BackgroundImageLayout = ImageLayout.Stretch;
                //INSERT CODE HERE: to remove from other if it has
            break;
        case "2":
            pb.BackgroundImage = Properties.Resources.OtherImg; //creates the background
            pb.BackgroundImageLayout = ImageLayout.Stretch;
                //INSERT CODE HERE: to remove from other if it has
            break;
        }
     }

我需要可以应用于多个图片框/对象的代码，而不仅仅是两个

Answer 1

我想你也需要存储最后一个图片框的图像

PictureBox _lastPictureBox = null;
Image _lastPictureBoxImage = null;

private void Pic_Click(object sender, System.EventArgs e)
{
    PictureBox pb = (PictureBox)sender;
    if (_lastPictureBox != null) 
    {
      // update the previous one, eg:
       _lastPictureBox.BackgroundImage = _lastPictureBoxImage;
    }

    // now set it to the current one:
   _lastPictureBox = pb;
   _lastPictureBoxImage = pb.Image;
   switch (pb.Name)
   {
     case "1": 
       pb.BackgroundImage = Properties.Resources.OtherImg; //creates the background
       pb.BackgroundImageLayout = ImageLayout.Stretch;
    break;
    case "2":
      pb.BackgroundImage = Properties.Resources.OtherImg; //creates the background
      pb.BackgroundImageLayout = ImageLayout.Stretch;
    break;
  }

}

Answer 2

最简单的方法是在表单中添加一个成员，该成员将跟踪先前单击的 PictureBox：

PictureBox _lastPictureBox = null;

在处理程序中，检查 _lastPictureBox 是否有值，并根据需要进行更新：

private void Pic_Click(object sender, System.EventArgs e)
{
    PictureBox pb = (PictureBox)sender;
    if (_lastPictureBox != null) 
    {
        // update the previous one, eg:
        _lastPictureBox.BackgroundImage = Properties.Resources.FirstImg;
    }

    // now set it to the current one:
    _lastPictureBox = pb;

    switch (pb.Name)
    {
    case "1": 
        pb.BackgroundImage = Properties.Resources.OtherImg; //creates the background
        pb.BackgroundImageLayout = ImageLayout.Stretch;
        break;
    case "2":
        pb.BackgroundImage = Properties.Resources.OtherImg; //creates the background
        pb.BackgroundImageLayout = ImageLayout.Stretch;
        break;
    }
 }

Answer 3

如果我理解正确，你需要一个全局变量

PictureBox lastbox;

然后你可以插入这个代码：

lastbox.Image = Properties.Resources.Image;
lasbox = pb;