private void RemoveOutlineAt(SnapshotPoint snapshotPoint)
            {
                var            textBuffer = this.theHost.TextView.TextBuffer;
                IUserOutlining outlining  = UserOutliningManager.Get(textBuffer);

                if (outlining != null)
                {
                    outlining.RemoveAt(snapshotPoint);
                }
            }
        public ITagger <T> CreateTagger <T>(ITextBuffer buffer) where T : ITag
        {
            IOutliningManager manager = UserOutliningManager.GetManager(buffer);

            if (typeof(T) == typeof(IOutliningRegionTag))
            {
                return(manager.GetOutliningTagger() as ITagger <T>);
            }
            return(manager.GetGlyphTagger() as ITagger <T>);
        }