A step-by-step guide to implementing the Memento design pattern in C#, covering all six stages: defining the IMemento interface, building the TextEditor originator with a private nested memento class, creating a caretaker for snapshot management, adding undo functionality with a single stack, extending to full undo/redo with dual stacks, and writing xUnit tests. The guide also addresses common pitfalls such as capturing references instead of values, unbounded memory growth, and forgetting to clear the redo stack on new actions.
Table of contents
PrerequisitesStep 1: Define the IMemento InterfaceStep 2: Create the Originator ClassStep 3: Build the CaretakerStep 4: Implement Undo FunctionalityStep 5: Add Redo Support with Dual StacksStep 6: Unit Testing ApproachCommon Mistakes to AvoidFrequently Asked Questions429 Impressions