switch (pos)
{
    case 1:
        lineShape1.Visible = true;
        lineShape32.Visible = false;
        break;
    case 2:
        lineShape2.Visible = true;
        lineShape1.Visible = false;
        break;
    case 3:
        lineShape3.Visible = true;
        lineShape2.Visible = false;
        break;
    //cases repeated 32 times
}

CheckBox snabox = this.Controls["checkBox" + pos.ToString()] as CheckBox;
if (snabox.Checked)
{
    Snare_Click(null, null);
}

lineShapes[pos-1].Visible = true;
pos == 1 ? lineShapes[lineShapes.Length - 1].Visible = false : lineShapes[pos-2].Visible = false;