/// <summary>
/// 在将对象拖到控件的边界上发生。
/// </summary>
private void treeView_DragOver(object sender, DragEventArgs e)
{
// 计算拖动的位置并移动图片
Point point = this.tempTreeView.PointToClient(new Point(e.X, e.Y));
DragHelper.ImageList_DragMove(point.X - this.tempTreeView.Left, point.Y - this.tempTreeView.Top);
// 取得实际拖拽到目标节点
TreeNode nodeAt = this.tempTreeView.GetNodeAt(this.tempTreeView.PointToClient(new Point(e.X, e.Y)));
if (nodeAt == null)
{
e.Effect = DragDropEffects.None;
}
else
{
e.Effect = DragDropEffects.Move;
if (this.tempDropNode != nodeAt)
{
DragHelper.ImageList_DragShowNolock(false);
this.tempTreeView.SelectedNode = nodeAt;
DragHelper.ImageList_DragShowNolock(true);
this.tempDropNode = nodeAt;
}
TreeNode treeNode = nodeAt;
while (treeNode.Parent != null)
{
if (treeNode.Parent == this.dragNode)
{
e.Effect = DragDropEffects.None;
}
treeNode = treeNode.Parent;
}
}
}
