public void StartScanning() { Scanner device = null; this.Invoke(new MethodInvoker(delegate () { device = comboBox3.SelectedItem as Scanner; })); if (device == null) { MessageBox.Show("Nie wybrano skanera!", "Ostrzezenie", MessageBoxButtons.OK, MessageBoxIcon.Warning); return; } else if (String.IsNullOrEmpty(textBox2.Text)) { MessageBox.Show("Wprowadz nazwe pliku!", "Ostrzezenie", MessageBoxButtons.OK, MessageBoxIcon.Warning); return; } ImageFile image = new ImageFile(); string imageExtension = ""; device.SetResolution(resolution); this.Invoke(new MethodInvoker(delegate () { switch (comboBox1.SelectedIndex) { case 0: image = device.ScanPNG(); imageExtension = ".png"; break; case 1: image = device.ScanJPEG(); imageExtension = ".jpeg"; break; case 2: image = device.ScanTIFF(); imageExtension = ".tiff"; break; } })); // Save the image path = Path.Combine(textBox2.Text + imageExtension); if (File.Exists(path)) { File.Delete(path); } image.SaveFile(path); pictureBox1.Image = new Bitmap(path); }