如何删除在 C# 中创建的图像?

How to remove a created image in C#?

我有它,所以用户可以单击图像视图并将项目拖动到表单的其他位置,这样做会创建一个新图像,同时原始图像框保持不变。如何在点击时删除其中一张重复的图片?

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
        this.AllowDrop = true;
        this.pictureBox1.MouseDown += pictureBox1_MouseDown;
    }

    private void pictureBox1_MouseDown(object sender, MouseEventArgs e)
    {
        if (e.Button == MouseButtons.Left)
        {
            var dragImage = (Bitmap)pictureBox1.Image;
            IntPtr icon = dragImage.GetHicon();
            Cursor.Current = new Cursor(icon);
            DoDragDrop(pictureBox1.Image, DragDropEffects.Copy);
            DestroyIcon(icon);
        }
    }
    protected override void OnGiveFeedback(GiveFeedbackEventArgs e)
    {
        e.UseDefaultCursors = false;
    }
    protected override void OnDragEnter(DragEventArgs e)
    {
        if (e.Data.GetDataPresent(typeof(Bitmap))) e.Effect = DragDropEffects.Copy;
    }
    protected override void OnDragDrop(DragEventArgs e)
    {
        var bmp = (Bitmap)e.Data.GetData(typeof(Bitmap));
        var pb = new PictureBox();
        pb.Image = (Bitmap)e.Data.GetData(typeof(Bitmap));
        pb.Size = pb.Image.Size;
        pb.Location = this.PointToClient(new Point(e.X - pb.Width / 2, e.Y - pb.Height / 2));
        this.Controls.Add(pb);
    }

    [System.Runtime.InteropServices.DllImport("user32.dll")]
    extern static bool DestroyIcon(IntPtr handle);
}

拖拽后添加删除操作即可

        protected override void OnDragDrop(DragEventArgs e) {
        var pb = new PictureBox {
            Image = (Bitmap)e.Data.GetData(typeof(Bitmap))
        };
        pb.Size = pb.Image.Size;
        pb.Location = PointToClient(new Point(e.X - pb.Width / 2, e.Y - pb.Height / 2));
        Controls.Add(pb);
        // deletion here: Controls.Remove(pictureBox1 or pb);
        base.OnDragDrop(e);
    }

如果你想在其他地方删除它,你需要在class级别声明一个变量,并用'pb'赋值。然后你可以决定删除哪一个给定 pictureBox1 和 pb.