C# 利用SaveFileDialog儲存pictureBox1圖片於自設路徑

private void button1_Click(object sender, EventArgs e)
{
    try
    {
        SaveFileDialog saveFileDialog1 = new SaveFileDialog();
        saveFileDialog1.Filter = "Bitmap Image|*.bmp";
        saveFileDialog1.Title = "儲存圖片";
        saveFileDialog1.ShowDialog();
        if (saveFileDialog1.FileName != "")
        {
            System.IO.FileStream fs = (System.IO.FileStream)saveFileDialog1.OpenFile();
                
            switch (saveFileDialog1.FilterIndex)
            {
                case 1:
                    this.pictureBox1.Image.Save(fs,
                              System.Drawing.Imaging.ImageFormat.Bmp);
                    break;
            }
 
            fs.Close();
        }
    }
    catch (Exception ex)
    {
        MessageBox.Show(ex.Message);
    }
}