private void btnRead_Click(object sender, System.EventArgs e)
{
  OpenFileDialog ofd = new OpenFileDialog();
  ofd.ShowDialog();
  FileStream fs = new FileStream(ofd.FileName, FileMode.OpenOrCreate);
  StreamReader sr = new StreamReader(fs);
  int lineCount=0;
  while (sr.ReadLine()!=null)
  {
    lineCount++;
  }
  fs.Close();
  MessageBox.Show("There are " + lineCount + " lines in " + ofd.FileName);
}