using DevExpress.XtraTreeList;
using DevExpress.XtraTreeList.Nodes;
private void treeList1_DragDrop(object sender, System.Windows.Forms.DragEventArgs e)
{
TreeListNode dragNode, targetNode;
TreeList tl = sender as TreeList;
Point p = tl.PointToClient(new Point(e.X, e.Y));
dragNode = e.Data.GetData(typeof(TreeListNode)) as TreeListNode;
targetNode = tl.CalcHitInfo(p).Node;
tl.SetNodeIndex(dragNode, tl.GetNodeIndex(targetNode));
}