How to Convert a C# Class Library to a .NET MAUI Class Library

Converting a C# class library to a .NET MAUI class library involves a few steps. Here’s a step-by-step guide:

1. Update your development environment

First, ensure you have all the tools required for .NET MAUI development:

  • Visual Studio 2022 (17.3 or later) with the .NET MAUI workload installed.
  • .NET SDK (6.0 or later).

2. Create a new .NET MAUI Class Library Project

  1. Open Visual Studio.
  2. Create a new project.
  3. Choose the .NET MAUI Class Library template.
  4. Name your project and specify the location, then click Create.

3. Copy your existing code

  • Copy the code from your existing C# class library and paste it into the newly created .NET MAUI class library project.

4. Update Project File (.csproj)

You need to modify the project file to ensure it targets .NET 6.0 (or later) and supports MAUI.

Here is an example of what your .csproj might look like for a .NET MAUI class library:

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

  <PropertyGroup>
    <TargetFrameworks>net6.0-ios;net6.0-android;net6.0-maccatalyst;net6.0-windows10.0.19041.0</TargetFrameworks>
    <OutputType>Library</OutputType>
    <UseMaui>true</UseMaui>
    <!-- Describe the package -->
    <Description>My .NET MAUI Class Library</Description>
    <PackageTags>maui;library</PackageTags>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.Maui.Controls" Version="6.0.100" />
  </ItemGroup>

</Project>

5. Resolve Dependencies and References

  • Ensure that all the dependencies and references required by your C# class library are compatible with .NET MAUI and .NET 6.0 (or later).
  • Update NuGet packages if required.

6. Test the .NET MAUI Class Library

Before using your new .NET MAUI class library in an app, ensure it’s working correctly. You can create a simple .NET MAUI app project and reference your .NET MAUI class library to validate the functionality.

7. Address Platform-specific Code (if any)

If your original C# class library contains any platform-specific code:

  • Use conditional compilation symbols to ensure the code is only included on relevant platforms.
  • For example:
#if ANDROID
// Android-specific code here
#elif IOS
// iOS-specific code here
#endif

8. Build and Publish

  • Build the project to ensure there are no errors.
  • Publish the library if needed, using tools like NuGet.

Example of Testing the Library in a .NET MAUI App

  1. Create a new .NET MAUI App project or open an existing one.
  2. Add a reference to your .NET MAUI class library.
  3. Use the classes/methods from your library in the main app to ensure everything works as expected.

That’s it! You’ve successfully converted your C# class library to a .NET MAUI class library. If you face any issues, make sure to consult the .NET MAUI documentation or seek help from the developer community.