屏蔽鼠标滑轮滚动事件

cmbBuilding.MouseWheel += new MouseEventHandler(cmbBuilding_MouseWheel);

        private void cmbBuilding_MouseWheel(object sender, MouseEventArgs e)
        {
            System.Windows.Forms.HandledMouseEventArgs hme = (System.Windows.Forms.HandledMouseEventArgs)e;
            hme.Handled = true;
        }