private void examinar_Click(object sender, EventArgs e)
{
OpenFileDialog ofd
= new OpenFileDialog
();
ofd.Filter = "Fotografia(*.jpg)|*.jpg|Fotografia(*.jpeg)|*.jpeg";
if (ofd.ShowDialog() != DialogResult.OK) return;
int si=ofd.FileName.LastIndexOf('\');
int len=ofd.FileName.Length-(si);
string fName="C:\imagenes\" + ofd.FileName.Substring(si, len);
System.IO.File.Copy(ofd.FileName, fName);
picture.Image = Image.FromFile(fName);
}