private void TreeView_DragOver(object sender, DragEventArgs e)
{
TreeView tree = (TreeView)sender;
Point targetPoint = tree.PointToClient(new Point(e.X, e.Y));
TreeNode targetNode = tree.GetNodeAt(targetPoint);
DragDropInformation info = (DragDropInformation)e.Data.GetData(typeof(DragDropInformation));
if (info == null)
{
return;
}
TreeViewDragDropHelper.ImageList_DragMove(targetPoint.X, targetPoint.Y);
//TreeViewDragDropHelper.ImageList_DragMove(e.X, e.Y);
TreeNode sourceNode = info.SourceNode;
if (info.Client.IsDropAllowed(sourceNode, targetNode))
{
TreeViewDragDropHelper.ImageList_DragShowNolock(false);
tree.SelectedNode = targetNode;
e.Effect = e.AllowedEffect;
TreeViewDragDropHelper.ImageList_DragShowNolock(true);
}
else
{
TreeViewDragDropHelper.ImageList_DragShowNolock(false);
tree.SelectedNode = sourceNode;
e.Effect = DragDropEffects.None;
TreeViewDragDropHelper.ImageList_DragShowNolock(true);
}
}
private void ScrollDown(Point pt)
{
TreeNode visibleNode = this.TreeView.GetNodeAt(pt);
if (visibleNode == null)
{
return;
}
TreeNode showNode = visibleNode.NextVisibleNode;
if (showNode == null)
{
showNode = visibleNode.NextNode;
if (showNode == null)
{
showNode = visibleNode.Parent;
if (showNode != null)
{
showNode = showNode.NextNode;
}
}
}
if (showNode != null)
{
TreeViewDragDropHelper.ImageList_DragShowNolock(false);
showNode.EnsureVisible();
this.TreeView.Invalidate();
TreeViewDragDropHelper.ImageList_DragShowNolock(true);
}
}