There is a collection in which the user can add objects and delete them.

Tell me how you can implement the functionality of undo / redo changes using Ctrl + Z / Ctrl + Y?

I would be grateful for any suggestions and links.

    1 answer 1

    The classic solution to this problem is to use the command pattern.

    Suppose there is a code in the Execute() method that performs some useful action, and in the Undo() method there is a code that cancels this change (in your case, the collection changes are rolled back). You need a stack in which you will place such objects before calling the Execute() method on them and, accordingly, by Ctrl + Z you will unwind such a stack, causing the Undo() method of the operation to be rolled back

     public class Command { public void Execute() { // ΠžΠΏΠ΅Ρ€Π°Ρ†ΠΈΡ измСнСния ΠΊΠΎΠ»Π»Π΅ΠΊΡ†ΠΈΠΈ } public void Undo() { // ΠžΠΏΠ΅Ρ€Π°Ρ†ΠΈΡ ΠΎΡ‚ΠΊΠ°Ρ‚Π° измСнСния } }