FileExtension–plugins–part 3

What I have more in mind is that the people can add easy their code for extensions.

That means:

1. Have an easy class to add the magic number in the header for an extension
2. Have other people add their own implementations,not just the header
3. Have an easy way to add the project with their code

First item it is easy – just create a class RecognizeFirstBytes and pass into constructor the first bytes

As an example,see the sln implementation

    public class RecognizeSln : RecognizeFirstBytes
    {
        public RecognizeSln() : base("EFBBBF0D0A4D6963726F736F66742056697375616C2053747564696F20536F6C7574696F6E2046696C65")
        {
            Extension = new string[1] { "sln" };
        }
    }

The second item can be implemented with an interface IRecognize

    public interface IRecognize: IEquatable<IRecognize>
    {
        Result InfoNeeded(byte[] b=null);
        string[] Extension { get; set; }
    }

The third item can be made by  making a third project  that  either references all other projects,either loading others as plugins . Because of the experience,I choose the most interesting one – plugins. I need first https://github.com/natemcmaster/DotNetCorePlugins . Second I need the plugins to be copied – I use a Target

  <Target Name="PreBuild" BeforeTargets="PreBuildEvent">
    <Exec Command="xcopy "$(ProjectDir)../plugins/*.dll" "$(ProjectDir)plugins" /E /F /I /Y /R" />
  </Target>

And last I need this plugin loader,when packed as nuget  at https://www.nuget.org/packages/FileExtension/,to have also the plugins – for this I use the csproj

<ItemGroup>
  <Content Include="plugins\**\*.dll">
    <PackagePath>build\net5.0\plugins\</PackagePath>
    <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
  </Content>
</ItemGroup>