在Windows窗体中操作拖放图像c＃

Question

I am trying to write a program which will allow a user to drag and drop images into the program and then be able to select the image, move it about, re-size it, crop it etc.

So far I have created a windows form which consists of a panel. A user can drag a picture file onto the panel and a picturebox will be created at the coordinates of the mouse when it is dropped and an image is loaded in the picturebox. I can add several images in this fashion.

Now I want to allow the user to manipulate and move about the images that they have dropped into the panel.

I have tried searching for solutions but cant seem to find an answer which I understand.

Any help is much appreciated..

This is my current code

 private void panel1_DragEnter(object sender, DragEventArgs e)
    {
        e.Effect = DragDropEffects.All;
    }



    private void panel1_DragDrop(object sender, DragEventArgs e)
    {
        String[] imagePaths = (String[])e.Data.GetData(DataFormats.FileDrop);
        foreach (string path in imagePaths)
        {
            Point point = panel1.PointToClient(Cursor.Position);

            PictureBox pb = new PictureBox();
            pb.ImageLocation = path;
            pb.Left = point.X;
            pb.Top = point.Y;

            panel1.Controls.Add(pb);

            //g.DrawImage(Image.FromFile(path), point);
        }

    }

Answer 1

You can get the mouse position when the user initially clicks and then track the mouse position in the PictureBox's MouseMove event. You can attach these handlers to multiple PictureBoxes.

private int xPos;
private int yPos;

private void pb_MouseDown(object sender, MouseEventArgs e)
{
    if (e.Button == MouseButtons.Left)
    {
       xPos = e.X;
       yPos = e.Y;
    }
}

private void pb_MouseMove(object sender, MouseEventArgs e)
{
    PictureBox p = sender as PictureBox;

    if(p != null)
    {
        if (e.Button == MouseButtons.Left)
        {
            p.Top += (e.Y - yPos);
            p.Left +=  (e.X - xPos);
        }
    }
}

For dynamic PictureBoxes you can attach the handlers like this

PictureBox dpb = new PictureBox();
dpb.MouseDown += pb_MouseDown;
dbp.MouseMove += pb_MouseMove;
//fill the rest of the properties...