public override HistoryMemento PerformAction(DocumentWorkspace documentWorkspace)
        {
            string[]       fileNames;
            string         startingDir = Path.GetDirectoryName(documentWorkspace.FilePath);
            DialogResult   result      = DocumentWorkspace.ChooseFiles(documentWorkspace, out fileNames, true, startingDir);
            HistoryMemento retHA       = null;

            if (result == DialogResult.OK)
            {
                Type oldToolType = documentWorkspace.GetToolType();
                documentWorkspace.SetTool(null);

                retHA = ImportMultipleFiles(documentWorkspace, fileNames);

                Type newToolType;
                if (retHA != null)
                {
                    CompoundHistoryMemento cha = new CompoundHistoryMemento(StaticName, StaticImage, new HistoryMemento[] { retHA });
                    retHA       = cha;
                    newToolType = typeof(Tools.MoveTool);
                }
                else
                {
                    newToolType = oldToolType;
                }

                documentWorkspace.SetToolFromType(newToolType);
            }

            return(retHA);
        }
        public override HistoryMemento PerformAction(DocumentWorkspace documentWorkspace)
        {
            string[] fileNames;
            string startingDir = Path.GetDirectoryName(documentWorkspace.FilePath);
            DialogResult result = DocumentWorkspace.ChooseFiles(documentWorkspace, out fileNames, true, startingDir);
            HistoryMemento retHA = null;

            if (result == DialogResult.OK)
            {
                Type oldToolType = documentWorkspace.GetToolType();
                documentWorkspace.SetTool(null);

                retHA = ImportMultipleFiles(documentWorkspace, fileNames);

                Type newToolType;
                if (retHA != null)
                {
                    CompoundHistoryMemento cha = new CompoundHistoryMemento(StaticName, StaticImage, new HistoryMemento[] { retHA });
                    retHA = cha;
                    newToolType = typeof(Tools.MoveTool);
                }
                else
                {
                    newToolType = oldToolType;
                }

                documentWorkspace.SetToolFromType(newToolType);
            }

            return retHA;
        }