#cpp
...
private void onClick2(object sender, System.EventArgs args) { // Button2:"Push1"
  StringBuilder4.Clear();
  foreach (var ForEach5 in TextBox6.Text) {
    StringBuilder4.AppendFormat("{0}, ", ForEach5);
  }
  StringBuilder4.AppendLine();
  TextBox8.AppendText(StringBuilder4.ToString());
}

private void onClick9(object sender, System.EventArgs args) { // Button9:"Push2"
  StringBuilder4.Clear();
  foreach (var ForEach5 in TextBox6.Text) {
    StringBuilder4.AppendFormat("{0}, ", ForEach5);
  }
  StringBuilder4.AppendLine();
  TextBox8.AppendText(StringBuilder4.ToString());
}
...

#cpp
...
private void onClick2(object sender, System.EventArgs args) { // Button2:"Push1"
  Method4();
}

private void onClick11(object sender, System.EventArgs args) { // Button11:"Push2"
  Method4();
}

private void Method4()
{
  StringBuilder6.Clear();
  foreach (var ForEach7 in TextBox8.Text) {
    StringBuilder6.AppendFormat("{0}, ", ForEach7);
  }
  StringBuilder6.AppendLine();
  TextBox10.AppendText(StringBuilder6.ToString());
}
...