Best design pattern for “undo” feature [duplicate]

Answer 1

I'd vote in favor of Command pattern over Memento. Memento pattern would be much costlier then Command patterns for Undo/Redo functionality.

Capturing and Restoring object state will be quite an expensive affair compared to just doing or undoing an action on any compatible object.

Answer 2

I believe it should be Command design pattern.

Here is article about multilevel Undo/Redo with Command pattern.

EDIT: Here is second about multilevel Undo/Redo with Memento pattern.

So probably it can be done with both.

Answer 3

Check out the Memento Pattern