Public Class CommandManager 

public class CommandManager 

/*
         * Create an instance of CommandSimple and execute it.
         */
        private void buttonExecute_Click(object sender, EventArgs e)
        {
            // Acquire a lock on the workbook set.
            workbookView.GetLock();
 
            try
            {
                // Create a simple command.
                CommandSimple command = new CommandSimple(workbookView);
 
                // Execute the command.
                workbookView.ActiveCommandManager.Execute(command);
            }
            finally
            {
                // Release the lock on the workbook set.
                workbookView.ReleaseLock();
            }
        }
 
        /*
         * Undo the last executed command if there is one.
         */
        private void buttonUndo_Click(object sender, EventArgs e)
        {
            // Acquire a lock on the workbook set.
            workbookView.GetLock();
 
            try
            {
                // Undo the last undoable command.
                workbookView.ActiveCommandManager.Undo();
            }
            catch (Exception exc)
            {
                MessageBox.Show(
                    this, exc.Message, "Exception", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
            finally
            {
                // Release the lock on the workbook set.
                workbookView.ReleaseLock();
            }
        }
 
        /*
         * Demonstrate creating a simple undoable command which
         * toggles the display of gridlines.
         */
        private class CommandSimple : SpreadsheetGear.Windows.Forms.Command
        {
            private WorkbookView _workbookView;
            private bool _saveDisplayGridlines;
 
            public CommandSimple(WorkbookView workbookView)
                : base(workbookView.ActiveWorkbook)
            {
                _workbookView = workbookView;
            }
 
            public override string DisplayText
            {
                get
                {
                    // Text displayed in Undo menu.
                    return "Toggle Display Gridlines";
                }
            }
 
            public override CommandUndoSupport UndoSupport
            {
                get
                {
                    // Undo is fully supported.
                    return CommandUndoSupport.Full;
                }
            }
 
            protected override bool Execute()
            {
                // Verify that a lock has already been acquired.
                System.Diagnostics.Debug.Assert(_workbookView.ActiveWorkbookSet.HasLock);
 
                // Execute the command - we won't save state since we're
                // just toggling a boolean value.
                IWorksheetWindowInfo windowInfo = _workbookView.ActiveWorksheetWindowInfo;
                _saveDisplayGridlines = windowInfo.DisplayGridlines;
                windowInfo.DisplayGridlines = !_saveDisplayGridlines;
                return true;
            }
 
            protected override bool Undo()
            {
                // Undo the command.
                _workbookView.ActiveWorksheetWindowInfo.DisplayGridlines = _saveDisplayGridlines;
                return true;
            }
        }