Best design pattern for "undo" feature [duplicate]

Question

Possible Duplicate:
Design Pattern for Undo Engine

In general, how do you deal with supporting an "undo" feature in your application? I have worked on web apps and desktop apps alike, and I have never really felt comfortable with any "undo" system I've made.

Answer 1

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.