private void timer_Tick(object sender, EventArgs e)
{
Point pt = PointToClient(Control.MousePosition);
TreeNode node = GetNodeAt(pt);
if (node == null)
{
return;
}
if (pt.Y < 30)
{
if (node.PrevVisibleNode != null)
{
node = node.PrevVisibleNode;
DragHelper.ImageList_DragShowNolock(false);
node.EnsureVisible();
Refresh();
DragHelper.ImageList_DragShowNolock(true);
}
}
else if (pt.Y > Size.Height - 30)
{
if (node.NextVisibleNode != null)
{
node = node.NextVisibleNode;
DragHelper.ImageList_DragShowNolock(false);
node.EnsureVisible();
Refresh();
DragHelper.ImageList_DragShowNolock(true);
}
}
}
private void treeView1_DragOver(object sender, DragEventArgs e)
{
Array a = (Array)e.Data.GetData(DataFormats.FileDrop);
Point formP = PointToClient(new Point(e.X, e.Y));
DragHelper.ImageList_DragMove(formP.X - Left, formP.Y - Top);
TreeNode dropNode = GetNodeAt(PointToClient(new Point(e.X, e.Y)));
if (dropNode == null && a == null)
{
e.Effect = DragDropEffects.None;
return;
}
e.Effect = DragDropEffects.Move;
if (_tempDropNode != dropNode)
{
DragHelper.ImageList_DragShowNolock(false);
SelectedNode = dropNode;
DragHelper.ImageList_DragShowNolock(true);
_tempDropNode = dropNode;
}
TreeNode tmpNode = dropNode;
if (tmpNode != null)
{
while (tmpNode.Parent != null)
{
if (tmpNode.Parent == _dragNode)
{
e.Effect = DragDropEffects.None;
}
tmpNode = tmpNode.Parent;
}
}
}
