1 files changed, 113 insertions, 0 deletions
diff --git a/mcs/class/Managed.Windows.Forms/System.Windows.Forms/OpenTreeNodeEnumerator.cs b/mcs/class/Managed.Windows.Forms/System.Windows.Forms/OpenTreeNodeEnumerator.cs
new file mode 100644
index 00000000000..32a79e93027
--- /dev/null
+++ b/mcs/class/Managed.Windows.Forms/System.Windows.Forms/OpenTreeNodeEnumerator.cs
@@ -0,0 +1,113 @@
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+//
+// Copyright (c) 2004 Novell, Inc.
+//
+// Authors:
+//	Jackson Harper (jackson@ximian.com)
+
+
+using System;
+using System.Collections;
+
+namespace System.Windows.Forms {
+
+	internal class OpenTreeNodeEnumerator : IEnumerator {
+
+		private TreeNode start;
+		private TreeNode current;
+		private bool started;
+
+		public OpenTreeNodeEnumerator (TreeNode start)
+		{
+			this.start = start;
+		}
+
+		public object Current {
+			get { return current; }
+		}
+
+		public TreeNode CurrentNode {
+			get { return current; }
+		}
+
+		public bool MoveNext ()
+		{
+			if (!started) {
+				started = true;
+				current = start;
+				return (current != null);
+			}
+
+			if (current.IsExpanded && current.Nodes.Count > 0) {
+				current = current.Nodes [0];
+				return true;
+			}
+
+			TreeNode prev = current;
+			TreeNode next = current.NextNode;
+			while (next == null) {
+				// The next node is null so we need to move back up the tree until we hit the top
+				if (prev.parent == null)
+					return false;
+				prev = prev.parent;
+				if (prev.parent != null)
+					next = prev.NextNode;
+			}
+			current = next;
+			return true;
+		}
+		
+		public bool MovePrevious ()
+		{
+			if (!started) {
+				started = true;
+				current = start;
+				return (current != null);
+			}
+
+			if (current.PrevNode != null) {
+				// Drill down as far as possible
+				TreeNode prev = current.PrevNode;
+				TreeNode walk = prev;
+				while (walk != null) {
+					prev = walk;
+					if (!walk.IsExpanded)
+						break;
+					walk = walk.LastNode;
+				}
+				current = prev;
+				return true;
+			}
+
+			if (current.parent == null ||
+					current.parent == current.TreeView.root_node)
+				return false;
+
+			current = current.parent;
+			return true;
+		}
+
+		public void Reset ()
+		{
+			started = false;
+		}
+	}
+}
+