about checkbox in windows

hi.
add the following code in Allchkbox's checkedchanged event
and initially set both check box visibility as false

private void Allchkbox_CheckedChanged(object sender, EventArgs e)
        {
            checkBox2.Visible = true;
            checkBox3.Visible = true;
            checkBox2.Enabled = false;
            checkBox3.Enabled = false;
        }