private void EnterTextBox_KeyDown(object sender, KeyEventArgs e)
{
switch (e.KeyCode)
{
case Keys.Enter:
Button1_Click(this, new EventArgs());
break;
case Keys.Up:
e.Handled = true;
string prevCommand = commands.GetPrevious();
textBox1.Text = prevCommand;
textBox1.SelectionStart = prevCommand.Length;
break;
case Keys.Down:
e.Handled = true;
string nextCommand = commands.GetNext();
textBox1.Text = nextCommand;
textBox1.SelectionStart = nextCommand.Length;
break;
}
}