Blazor and Razor are two remarkable technologies when it comes to .NET-based web application development. Ever since Blazor first came to light, many developers have been wondering about the difference and relationship between these two frameworks.

This article will explore the shared attributes of these two technologies, how they interact, the significant ways in which they differ, the advantages and disadvantages of using each of these technologies, and several use cases.

What is Blazor?

Blazor is a component-based, single-page app framework that works with all modern-day web browsers, including mobile browsers. The main difference between other popular web frameworks and Blazor is that the latter uses C# instead of JavaScript to build web apps, allowing developers to create both the client-side and server-side of the app using the same language, C#.

Like React, Blazor uses a reusable component-based structure to build UI components that we can use over multiple pages. In addition, Blazor comprises two different hosting models, Blazor WebAssembly and Blazor Server.

Blazor WebAssembly: When Blazor WebAssembly (WASM) is used, all the processing is done on the client-side by downloading the dependencies and the .NET runtime to the browser. Because of this, there is no need for constant connection with the server. We can create the client-side pages using Razor Pages or Razor components.

Blazor Server: As the name suggests, the app is hosted on a server from within the standard ASP.NET Core app. Unlike in Blazor WebAssembly, this needs a constant connection between the Blazor server app and the browser through SignalR.

What is Razor?

Razor also uses C# and HTML, just like Blazor, which confuses users as to why there are both Blazor and Razor. However, Razor is quite efficient in creating logical aspects in HTML without using JavaScript, and it is a templating engine for building dynamic webpages.

Another concept called Razor Pages shows more relation to ASP.NET MVC than Blazor. Razor Pages follow a file-based routing approach and contain specific code behind individual pages. Instead of the MVC, Razor pages use the MVVM model (Model-View-ViewModel) by abandoning the Controller component and using ViewModel instead.

Relationship between Razor and Blazor

As the name of Blazor itself comes from combining the two terms “Browser” and “Razor”, we can see that there’s a relationship between the two.

Both Razor and Blazor are Microsoft products that use C# and HTML to develop web apps. They are free and open-source, allowing developers to quickly and freely use these technologies. We use the Razor syntax when creating ASP.NET web apps, where Blazor shows more similarity to ASP.NET Core and ASP.NET MVC.

Blazor uses Razor as the template syntax for creating user interfaces, making Blazor act as a client-side hosting model for Razor components. Using Razor-based components with Blazor allows developers to break down individual features into tiny, easy-to-build components and then assemble these components to build a much larger app efficiently.

Pros and cons

Blazor and Razor are both quite popular when it comes to building .NET-based interactive web apps. These technologies bring a new way of going from traditional JavaScript apps to using C# as the fundamental programming language.

Following are a few advantages and disadvantages of Razor and Blazor to consider when building a web app.

Advantages of using Blazor

• Client-side Blazor runs .NET code directly on the browser using WebAssembly, which is fast and uses less network bandwidth.
• Server-side Blazor is compatible with all the .NET libraries and .NET tooling and has the same syntax as client-side Blazor.

Disadvantages of using Blazor

• Client-side Blazor does not support much .NET tooling or debugging and requires shipping the entire runtime.
• Server-side Blazor does not have the performance benefits that client-side Blazor has. Read more here.

Advantages of using Razor

• Razor allows embedding C# code into webpages to implement the logical aspects.
• Highly flexible, which makes Razor suitable to build a variety of apps.
• Highly organized structure and with specific code-behind pages.

Disadvantages of using Razor

• For client-side logic, using JavaScript is essential in Razor.
• Maintaining and handling multiple self-contained pages can be a challenge.

Main differences between Razor and Blazor

• Razor supports server-side templating and handling API logic but not the client-side logic outside JavaScript.
• Blazor is like a successor to Razor, enabling developers to handle both client-side and server-side logic using only C#.
• Razor is a template markup syntax. It embeds server-based code into the HTML. In contrast, Blazor is a SPA framework that runs on either Blazor WebAssembly or the Blazor Server, depending on the requirement.

When to use Razor

• Ideal for server-side, cross-platform HTML generation.
• Perfect for developing simple web pages when the content is properly structured.
• Best for small but action-based web pages.

When to use Blazor

• When there is a need to create robust UI components for a single-page app with a fast turnaround time.
• When there are fewer developers, Blazor does not require both front-end and back-end developers separately.
• When the developers need to create the whole project with C# as the programming language without using any JavaScript. (We can use JavaScript if needed through JavaScript interop). For more information, refer to the article Pros and Cons of Using JavaScript Interop in Blazor.

Conclusion

This article discussed the relationship and the differences between Blazor and Razor. One may need to know these things when figuring out when and where to use each. However, there is no doubt that both technologies are pretty helpful and fantastic for web app development. Blazor is ideal for building interactive web apps, and Razor makes it possible to combine the logical aspects by embedding C# into HTML CSS components.

Blazor and Razor are constantly being updated, and with their massive community of developers, these two technologies are surely conquering the web development industry. So, I hope this article gave you a good understanding of Blazor and Razor and the interaction between these two remarkable technologies.

Thank you for reading!

Syncfusion’s Blazor component suite offers over 70 UI components that work with both server-side and client-side (WebAssembly) hosting models seamlessly. Use them to build marvelous apps!

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