DevExpress GridView中将MultiSelect设为True后，禁用鼠标拖动选择多行的功能，而保留ctrl shift的多选功能

最近项目中遇到一个需求--拖动表格行进行排序，当把GridView中MultiSelect设为false时很正常，但把MultiSelect设为True后，拖动时会选中多行，经研究找到以下解决方法：

思路是重写**OnMouseMove、OnMouseUp**方法，**OnMouseMove重写时将MultiSelect设为False,OnMouseUp重写再将MultiSelect设为True**。

这样既不影响拖动效果（拖动排序时不会再选中多行），拖动排序完后，又能正常多选进行删除行等操作，完整代码如下：

 

public partial class DraggableGridControl : DevExpress.XtraGrid.GridControl
{
    GridView gridView = null;
    Point m_mouseDownLocation;
    int m_dragHandle;
    DragForm m_dragRowShadow;
    bool multiSelectFlag = false;

    protected override void OnMouseDown(MouseEventArgs ev)
    {
        if (ev.Button == MouseButtons.Left)
        {
            if (gridView == null)
            {
                gridView = ((GridView)base.MainView);
            }
            var _hit = gridView.CalcHitInfo(ev.Location);
            if (_hit.RowHandle >= 0)
            {
                m_dragHandle = _hit.RowHandle;
                m_mouseDownLocation = ev.Location;
            }
            else
            {
                m_dragHandle = -1;
            }
        }

        base.OnMouseDown(ev);
    }

    protected override void OnMouseMove(MouseEventArgs ev)
    {
        if (ev.Button == MouseButtons.Left && m_dragHandle >= 0)
        {
            if (m_dragRowShadow == null)
            {
                double _x2 = Math.Pow((ev.Location.X - m_mouseDownLocation.X), 2);
                double _y2 = Math.Pow((ev.Location.Y - m_mouseDownLocation.Y), 2);
                double _d2 = Math.Sqrt(_x2 + _y2);
                if (_d2 > 3)
                {
                    //执行拖拽；
                    this.BeginDrag(m_dragHandle);
                }
            }
            else
            {
                m_dragRowShadow.Location = new Point(m_dragRowShadow.Location.X, this.PointToScreen(ev.Location).Y);
            }
        }
        base.OnMouseMove(ev);
    }

    protected override void OnMouseUp(MouseEventArgs ev)
    {
        if (m_dragRowShadow != null)
        {
            var _hit = gridView.CalcHitInfo(ev.Location);
            this.EndDrag(_hit.RowHandle);
        }

        base.OnMouseUp(ev);
    }

    private void BeginDrag(int _handle)
    {
        if (gridView.OptionsSelection.MultiSelect == true)
        {
            multiSelectFlag = true;
            gridView.OptionsSelection.MultiSelect = false;
        }

        var _info = (DevExpress.XtraGrid.Views.Grid.ViewInfo.GridViewInfo)gridView.GetViewInfo();
        Rectangle _bound = _info.GetGridRowInfo(_handle).Bounds;
        _bound.Location = this.PointToScreen(_bound.Location);
        m_dragRowShadow = new DragForm(_bound);
        m_dragRowShadow.Show();
    }

    private void EndDrag(int _handle)
    {
        if (m_dragRowShadow != null)
        {
            m_dragRowShadow.Close();
            m_dragRowShadow.Dispose();
            m_dragRowShadow = null;

            int _rowIndex = gridView.GetDataSourceRowIndex(m_dragHandle);

            DataRow _row = ((DataTable)this.DataSource).Rows[_rowIndex];
            object[] _values = _row.ItemArray;

            base.BeginUpdate();

            //移除目标行；
            ((DataTable)this.DataSource).Rows.RemoveAt(m_dragHandle);
            _row = ((DataTable)this.DataSource).NewRow();
            _row.ItemArray = _values;
            if (_handle >= 0)
            {
                //插入指定位置；
                ((DataTable)this.DataSource).Rows.InsertAt(_row, _handle);
                gridView.FocusedRowHandle = _handle;
            }
            else
            {
                //添加；
                ((DataTable)this.DataSource).Rows.Add(_row);
                gridView.FocusedRowHandle = gridView.RowCount - 1;
            }

            base.EndUpdate();

            if (multiSelectFlag)
                gridView.OptionsSelection.MultiSelect = true;
        }
    }
}