private void OpenButton_Click(object sender, EventArgs e) { try { if (ResultImage.Image == null) { openFile.Filter = "Image Files(*.PNG)|*.PNG"; if (openFile.ShowDialog() == DialogResult.OK) { sFileName = openFile.FileName; FileName.Text = sFileName; image = new Bitmap(openFile.FileName); if (image.Size.Height == 256 && image.Size.Width == 256) { SourceImage.Image = image; SourceImage.Invalidate(); FileInfo imageInfo = new FileInfo(sFileName); sourceSizeInKBytes = Convert.ToInt32(imageInfo.Length / 1024); } else { DialogResult rezult = MessageBox.Show("Incorrect image size! Try again.", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); } } } else { DialogResult rezult = MessageBox.Show("You can't open image now.", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Warning); } } catch (Exception exception) { DialogResult rezult = MessageBox.Show("Error opening image!", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); } }