Microsoft.VisualStudio.Project.ProjectNode.CreateFolderNode C# (CSharp) Method

        protected internal FolderNode CreateFolderNode(string path)
        {
            ProjectElement item = this.AddFolderToMsBuild(path);
            FolderNode folderNode = CreateFolderNode(path, item);
            return folderNode;
        }

        private static void AddNonMemberFolderItems(ProjectNode project, IEnumerable<string> folderList)
        {
            ErrorHelper.ThrowIsNull(folderList, "folderList");

            foreach (string folderKey in folderList)
            {
                HierarchyNode parentNode = project;
                string[] folders = folderKey.Split(Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar);
                NemerleFolderNode topFolderNode = null;
                foreach (string folder in folders)
                {
                    string childNodeId = Path.Combine(parentNode.VirtualNodeName, folder);
                    FileInfo folderInfo = new FileInfo(Path.Combine(project.ProjectFolder, childNodeId));
                    if ((folderInfo.Attributes & FileAttributes.Hidden) == FileAttributes.Hidden)
                        break;

                    HierarchyNode childNode = parentNode.FindChild(childNodeId);
                    if (childNode == null)
                    {
                        if (topFolderNode == null)
                        {
                            topFolderNode = parentNode as NemerleFolderNode;
                            if (topFolderNode != null && (!topFolderNode.IsNonMemberItem) && topFolderNode.IsExpanded)
                                topFolderNode = null;
                        }

                        ProjectElement element = new ProjectElement(project, null, true);
                        childNode = project.CreateFolderNode(childNodeId, element);
                        parentNode.AddChild(childNode);
                    }

                    parentNode = childNode;
                }

                if (topFolderNode != null)
                    topFolderNode.CollapseFolder();
            }
        }