private void textBox1_keypress(object sender, KeyPressEventArgs k) { k.Handled = true; if ((k.KeyChar >= '0' && k.KeyChar <= '9') || k.KeyChar == '\t' || k.KeyChar == '\b' || k.KeyChar == '\r') { k.Handled = false; } if (k.KeyChar == '\r') { monthCalendar1.Focus(); } }