.NET Q & A


What is the Razor Class Library (RCL)?

The Razor Class Library (RCL) is a powerful feature introduced in ASP.NET Core that allows developers to create reusable collections of Razor-based components, pages, views, and other related files in a single library project. It enables the encapsulation and distribution of UI components and related assets across multiple ASP.NET Core applications, promoting code reuse, modularity, and maintainability.


Reusable UI Components:

The primary purpose of the Razor Class Library is to facilitate the creation of reusable UI components and assets, such as pages, views, partial views, tag helpers, Razor components, CSS files, JavaScript files, and other related resources. Developers can encapsulate UI logic, markup, and styles into a single library project and share it across multiple applications.


Separation of Concerns:

RCL promotes the separation of concerns by allowing developers to isolate UI-related code and assets from application-specific logic and dependencies. It encourages a modular architecture where UI components can be developed, tested, and versioned independently of the main application, enhancing code maintainability and flexibility.


Distribution and Versioning:

Razor Class Libraries can be packaged as NuGet packages, making it easy to distribute and consume UI components across different projects and teams. Developers can version RCLs independently, manage dependencies, and update components seamlessly using standard package management tools and workflows.


Integration with ASP.NET Core Applications:

RCLs seamlessly integrate with ASP.NET Core applications, allowing developers to reference and use Razor components and assets from the library within their application projects. RCLs can be referenced as dependencies, and their components can be used in views, layouts, and other UI elements without any additional configuration.


Cross-Cutting Concerns and Theming:

RCLs are well-suited for managing cross-cutting concerns such as UI theming, branding, and common UI patterns across multiple applications. Developers can create RCLs that define shared styles, layouts, and components consistent with the organization’s branding guidelines and apply them uniformly across all applications.


Testability and Maintenance:

By encapsulating UI components and related assets into RCLs, developers can improve the testability and maintainability of their applications. RCLs enable centralized testing of UI components, promote code reuse, reduce duplication, and simplify maintenance efforts by consolidating common UI logic and assets in a single location.


The Razor Class Library (RCL) is a valuable tool for creating and distributing reusable UI components and assets in ASP.NET Core applications. It promotes modularity, separation of concerns, code reuse, and maintainability, enabling developers to build scalable and maintainable web applications more efficiently.

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