Adding Razor Component Support

September 12, 2021 · View on GitHub

If you have a .NET Standard class library you can add support for Razor Components to these by following these steps:

.NET Standard 2.0

1. SDK

Change the default project SDK from

<Project Sdk="Microsoft.NET.Sdk">

to the Razor SDK:

<Project Sdk="Microsoft.NET.Sdk.Razor">

2. RazorLangVersion

Add the <RazorLangVersion> tag to the <PropertyGroup>, e.g.:

  <PropertyGroup>
    <TargetFramework>netstandard2.0</TargetFramework>
    <RazorLangVersion>3.0</RazorLangVersion>
  </PropertyGroup>

3. Add Packages

Include these two NUGET packages in the package references

  <ItemGroup>
    <PackageReference Include="Microsoft.AspNetCore.Components" Version="3.1.14" />
    <PackageReference Include="Microsoft.AspNetCore.Components.Web" Version="3.1.14" />
  </ItemGroup>

4. Add an `_Imports.razor` file

Create a file called _Imports.razor in the root of the project, containing this:

@using Microsoft.AspNetCore.Components.Web

This file is used by the Razor tooling to import default namespaces into components, so common namespaces such as the one above are automatically in scope. It's not always required but useful to avoid needing to add @using .. statements to components repeatedly.

These steps replicate the changes made for Razor Class Libraries.

Other Project Types

Most applications using .NET Core 3.1 or higher, based on <Project Sdk="Microsoft.NET.Sdk"> can be updated to support Razor Components. I created a test Console application BlazorTemplater.ConsoleApp and applied the steps above, and it can render the Sample.razor component as HTML.