private void picCommodity_Click(object sender, EventArgs e)
        {
            pnlMID.Controls.Clear();
            FrmSellThing frm1 = new FrmSellThing();

            frm1.TopLevel = false;
            pnlMID.Controls.Add(frm1);
            frm1.Show();
        }
        private void picCommodity_Click(object sender, EventArgs e)
        {
            //picReser.BackgroundImage = Resources.预约管理;
            picRoom.BackgroundImage      = Resources.预订管理_aa;
            picCustomer.BackgroundImage  = Resources.用户管理_ib;
            picExtend.BackgroundImage    = Resources.扩展功能_ib;
            picCommodity.BackgroundImage = Resources.商品消费_ib;
            pnlMID.Controls.Clear();
            FrmSellThing frm1 = new FrmSellThing();

            frm1.TopLevel = false;
            pnlMID.Controls.Add(frm1);
            frm1.Show();
        }