C# Q & A


How to create reusable Razor components in C#?

Creating reusable Razor components in C# is a powerful way to modularize and share UI functionality across your ASP.NET Core applications. Razor components are self-contained, reusable building blocks for your web application’s user interface. Here’s a step-by-step guide on how to create them:


  1. Create a Razor Component:

   Start by creating a new Razor component. You can do this by adding a `.razor` file to your project. A Razor component consists of a combination of HTML markup and C# code. For example, you can create a `Button.razor` component that renders a customizable button.


  1. Define Parameters:

   Razor components often accept parameters to make them flexible and customizable. You can define parameters by adding properties to your component’s code section. These properties allow you to pass data from the parent component to the child component. For our `Button.razor` example, you might define parameters like `Text` and `OnClick` to specify the button’s label and click event handler.


  1. Markup and Logic:

   Within your Razor component, you can use HTML markup to define the component’s visual representation. You can also use C# code to implement the component’s logic. For instance, you might use a `@if` statement to conditionally render certain parts of the component based on the provided parameters.


  1. Render the Component:

   To use the Razor component in your views or pages, you simply include it using the component’s tag name, similar to an HTML element. Pass the required parameters to configure the component’s behavior. For example, `<Button Text=”Click me” OnClick=”HandleButtonClick” />` would render a button with the specified label and attach the `HandleButtonClick` method as the click event handler.


  1. Reusability:

   The beauty of Razor components lies in their reusability. You can use the same `Button.razor` component in multiple places throughout your application, ensuring a consistent UI element and behavior. If you need to make changes or updates, you can do so in one place, and those changes will propagate to all instances of the component.


  1. Testing and Validation:

   Ensure that your Razor components are thoroughly tested to validate their functionality. You can write unit tests to verify that the component behaves as expected, especially when different parameters are provided.


  1. Documentation:

   Properly document your Razor components, including details on how to use them, what parameters they accept, and any customization options available.


By following these steps, you can create reusable Razor components in C# that enhance the modularity and maintainability of your ASP.NET Core applications, while also providing a consistent and efficient way to build your user interface.


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Experienced Backend Developer with 6 years of experience in C#. Proficient in C#, .NET, and Java.Proficient in REST web services and web app development.