c# - 基于其他程序集类生成源码（c#源码生成器）

Question

我想生成一个静态类，该类应该有一个方法，具体取决于特定参考程序集中的其他类。

一个简化的例子：

// Generator.csproj
[Generator]
   public class MyGenerator : ISourceGenerator
   {
      public void Initialize(GeneratorInitializationContext context)
      {
          // Register a factory that can create our custom syntax receiver
          context.RegisterForSyntaxNotifications(() => new MySyntaxReceiver());
      }

      public void Execute(GeneratorExecutionContext context)
      {
          // var syntaxReceiver = (MySyntaxReceiver)context.SyntaxReceiver;
      }
   }

    private class MySyntaxReceiver : ISyntaxReceiver
    {
       ....
    }

// Core.csproj
// namespace Core.Entities
class Entity1 : IAccessControl {}
class Entity2  {}
class Entity3 : IAccessControl {}

// Persistence.csproj => has a reference to Core project and the Generator
// this class should be generated ...
static class GeneratedClass
{
   public static void DoSomethingEntity1()
   public static void DoSomethingEntity3()
}

我想在项目中找到Entity类并在Core项目中生成一个类Persistence，问题是我的Core项目无法访问并且之前已经编译过Persistence。我应该使用反射还是手动读取核心实体？还是有更好的方法来访问项目中的 SyntaxTree Core？

Answer 1

因为Core项目已经编译，我们无法访问 SyntaxTree，但我们可以通过编译来获取引用的程序集，然后查看这些程序集并找到符号。

public void Execute(GeneratorExecutionContext context)
{
// finding Core reference assembly Symbols
 IAssemblySymbol assemblySymbol = 
context.Compilation.SourceModule.ReferencedAssemblySymbols.First(q => q.Name == "Core");

// use assembly symbol to get namespace and type symbols
// all members in namespace Core.Entities
var members = assemblySymbol.GlobalNamespace.
                             GetNamespaceMembers().First(q => q.Name == "Core")                                       
                            .GetNamespaceMembers().First(q => q.Name == "Entities")
                            .GetTypeMembers().ToList();

var targets = new HashSet<INamedTypeSymbol>();

// find classes that implemented IAccessControl
foreach (var member in members.Where(m => m.AllInterfaces.Any(i => i.Name == "IAccessControl")))
{
   targets.Add(member); // Entity1 Entity3
}


// generate source using targets ...
// context.AddSource("GeneratedClass", source);
}

希望这个例子对其他人有所帮助。