Hey there! Let's break down both options to help you pick the right fit for your simple app.

Frame + Page #

• Strengths: This shines if you think your app might expand to need navigation history (like forward/back buttons) or multi-level page navigation later. WPF's Frame comes with a built-in NavigationService that handles all that out of the box—no custom logic needed for tracking user navigation paths. Pages also have dedicated lifecycle events (NavigatedTo, NavigatedFrom) that make it easy to load/unload data when switching views.
• Drawbacks: It’s a slightly heavier model. If you only need basic content switching without navigation history, you’ll be carrying unused functionality that adds unnecessary complexity to your code.

ContentControl + UserControl #

• Strengths: This is the lighter, more flexible choice for straightforward content switching. All you need to do is bind a ContentControl's Content property to a view model property (e.g., CurrentActiveView), then swap out the UserControl instance assigned to that property when a menu item is clicked. No extra navigation overhead, just direct control over your content. It’s perfect for apps where you only need to flip between sections without tracking user movement.
• Drawbacks: There’s no built-in navigation history. If you later decide to add forward/back features, you’ll have to build that logic yourself (like using a stack to keep track of previous views).

Recommendation for Your Simple App #

Since you’ve described your app as simple with just menu-triggered content switching, I’d recommend the ContentControl + UserControl approach. It’s simpler to implement, has less boilerplate code, and aligns perfectly with your current needs. If you ever need to add navigation features down the line, refactoring to use Frame + Page is totally feasible—but for now, keep it light!

内容的提问来源于stack exchange，提问作者RezaNoei