How to find the relative file path of a class file to csproj in SourceGenerator

I am using SourceGenerator and analysing a class to create a string that needs to have the relative path of the class file to the csproj file.

I am able to find the absolute path of the class file using code below, but not the relative path

public class XamlControlAndPageFinder : ISyntaxContextReceiver
{

    public void OnVisitSyntaxNode(GeneratorSyntaxContext context)
    {
        if (context.Node is ClassDeclarationSyntax userControl)
        {
             // This gives us the complete path and not relative path
             var filePath = userControl.SyntaxTree.FilePath;
        }
    }
}