使用Zoom SizeMode从缩放的图片框中获取正确的坐标

Question

1. I loaded the jpg to picture box (in SizeMode as Zoom).
2. I drew a rectangle on the picture box and took the coordinate.
3. I opened the jpg in paint and observed the coordinate (where I drew the rectangle on the picture box).

When I compared the rectangle coordinates (x and y) with paint coordinates, they were not the same.

I changed the SizeMode to Normal and observed that the coordinates became the same, but the image size was too large so it was display partially, so I want to use Zoom SizeMode property.

Say image with size 2825x3538 and keep the picture box size mode as Normal, the image shows partially in picture box. So I changed picture box mode to Zoom (to fit the System screen resolution), and the coordinates missmatched when comparing it with Normal mode with SizeMode.

How can I achieve the same coordinates?

private void openToolStripMenuItem_Click(object sender, EventArgs e)
{
    OpenFD.FileName = "";
    OpenFD.Title = "open image";
    OpenFD.InitialDirectory = "C";
    OpenFD.Filter = "JPEG|*.jpg|Bmp|*.bmp|All Files|*.*.*";
    if (OpenFD.ShowDialog() == DialogResult.OK)
    {
        file = OpenFD.FileName;
        image = Image.FromFile(file);
        pictureBox1.Image = image;
        svc = Screen.PrimaryScreen;
        pictureBox1.Width = svc.Bounds.Width;
        pictureBox1.Height = svc.Bounds.Height - 100;
        mybitmap1 = new Bitmap(pictureBox1.Image);
        mybitmap1.SetResolution(300, 300);
        pictureBox1.Image = mybitmap1;
    }
}

private void pictureBox1_MouseDown(object sender, MouseEventArgs e)
{
    if (mybitmap == null)
    {
        mybitmap = new Bitmap(pictureBox1.Width, pictureBox1.Height);
        mybitmap.SetResolution(300, 300);
    }
 }

private void pictureBox1_Paint(object sender, PaintEventArgs e)
{
    using (g = Graphics.FromImage(mybitmap))
    {
        using (Pen pen = new Pen(Color.Green, m))
        {
            e.Graphics.DrawRectangle(pen, r);
            e.Graphics.DrawString(lab[c].ToString(), new Font(lab[c].ToString(), 8F), new SolidBrush(label1.ForeColor), r);
        }
    }
}

Answer 1

您可以在实际图像和图片框之间使用两个比例因子，一个比例因子用于高度，另一个比例因子用于宽度。