I would write something simple like this piece of code :
private void button2_Click(object sender, System.EventArgs e)
{
SaveFileDialog saveFileDialog1 = new SaveFileDialog();
saveFileDialog1.Filter = "JPeg Image|*.jpg|Bitmap Image|*.bmp|Gif Image|*.gif";
saveFileDialog1.Title = "Save an Image File";
saveFileDialog1.ShowDialog();
if(saveFileDialog1.FileName != "")
{
System.IO.FileStream fs =
(System.IO.FileStream)saveFileDialog1.OpenFile();
switch(saveFileDialog1.FilterIndex)
{
case 1 :
this.button2.Image.Save(fs,
System.Drawing.Imaging.ImageFormat.Jpeg);
break;
case 2 :
this.button2.Image.Save(fs,
System.Drawing.Imaging.ImageFormat.Bmp);
break;
case 3 :
this.button2.Image.Save(fs,
System.Drawing.Imaging.ImageFormat.Gif);
break;
}
fs.Close();
}
}