ASP.NET中.razor与.cshtml文件的区别及Razor组件选型建议

Great question! I’ve helped tons of developers sort through this when transitioning between traditional ASP.NET and Blazor, so let’s break this down clearly.

Core Purpose & Runtime Model #

First, the biggest difference is what these files are built for:

• .cshtml: This is the workhorse of traditional ASP.NET MVC and Razor Pages. It’s a server-side rendering (SSR) template that runs entirely on the server. Every request triggers the server to generate full HTML, which gets sent to the browser. It’s tightly coupled to HttpContext, controllers, or page models, and relies on server-side logic to render dynamic content.
• .razor: This is the component file for Blazor (both Server and WebAssembly). It’s built for componentized UI development—think reusable, self-contained UI units with their own state, events, and lifecycle. Depending on your Blazor mode, it either runs on the server (via SignalR for real-time browser communication) or directly in the browser’s .NET runtime (WASM), cutting down on server roundtrips for most interactions.

Technical Differences in Practice #

Let’s get into the day-to-day differences you’ll notice:

• Data & Logic Binding:
  • .cshtml uses @model to bind to a page/model class, relies on ViewData/ViewBag for passing data, and uses @Html helper methods for rendering. It’s tied to the request-response cycle.
  • .razor uses component parameters ([Parameter] attribute) to pass data, supports two-way binding with @bind, and keeps logic in an @code block (or a separate .razor.cs partial class). It has lifecycle methods like OnInitializedAsync for handling component setup.
• Reusability:
  • .cshtml reuses content via partial views or layouts, but this is mostly page-level or section-level reuse.
  • .razor components are designed from the ground up to be reusable—you can create a single CustomButton.razor component and drop it anywhere in your app, with configurable props and behavior.
• Deployment & Environment:
  • .cshtml requires an ASP.NET server to run; it can’t execute client-side.
  • Blazor WASM’s .razor components can be deployed as static files (no backend server required, unless you need to call APIs), while Blazor Server still needs a server but handles interactions via SignalR instead of full page reloads.

Should You Replace .cshtml with .razor in Razor Component Apps? #

It depends on your project context:

• New Blazor Apps: Absolutely. .razor is the native way to build Blazor UIs. Using components gives you modular, maintainable code, and lets you leverage Blazor’s SPA-like capabilities (no full page reloads, client-side state management).
• Existing MVC/Razor Pages Apps: No need to do a full rewrite. Blazor can coexist with traditional ASP.NET—you can embed .razor components into .cshtml pages using the <component> tag, allowing you to migrate parts of your app incrementally.
• SEO-Focused or Static Content: If your app needs heavily optimized SEO (like a blog or marketing site) or mostly static content with minimal interactivity, .cshtml (Razor Pages) might still be a better fit, since SSR delivers fully rendered HTML to search engines faster.

内容的提问来源于stack exchange，提问作者BALA MURUGAN