基于其他程序集类生成源代码c#源代码生成器

问题描述

我想生成一个静态类,该类应该具有依赖于特定引用程序集中的其他类的方法

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Entity项目中找到Core类并在Persistence项目中生成一个类, 问题是我的 Core 项目无法访问并且它已经在 Persistence 之前编译。我应该使用反射还是手动阅读核心实体?或者有没有更好的方法来访问 Core 项目中的 SyntaxTree?

解决方法

由于 Core 项目已经编译,我们无法访问 SyntaxTree,但我们可以通过编译获取引用的程序集,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);
}

希望这个例子能帮助其他人。