void RemoveNodes(SharpTreeNode start, SharpTreeNode end)
{
// Removes all nodes from start to end (inclusive)
// All removed nodes will be reorganized in a separate tree, do not delete
// regions that don't belong together in the tree model!
List <SharpTreeNode> removedSubtrees = new List <SharpTreeNode>();
SharpTreeNode oldPos;
SharpTreeNode pos = start;
do
{
// recalculate the endAncestors every time, because the tree might have been rebalanced
HashSet <SharpTreeNode> endAncestors = new HashSet <SharpTreeNode>();
for (SharpTreeNode tmp = end; tmp != null; tmp = tmp.listParent)
{
endAncestors.Add(tmp);
}
removedSubtrees.Add(pos);
if (!endAncestors.Contains(pos))
{
// we can remove pos' right subtree in a single step:
if (pos.right != null)
{
removedSubtrees.Add(pos.right);
pos.right.listParent = null;
pos.right = null;
}
}
SharpTreeNode succ = pos.Successor();
DeleteNode(pos); // this will also rebalance out the deletion of the right subtree
oldPos = pos;
pos = succ;
} while (oldPos != end);
// merge back together the removed subtrees:
SharpTreeNode removed = removedSubtrees[0];
for (int i = 1; i < removedSubtrees.Count; i++)
{
removed = ConcatTrees(removed, removedSubtrees[i]);
}
}