C＃增量发电机 - 如何读取其他文件？额外的textsProvider无法正常工作

Question

我正在尝试从appsettings.json获得一些值。但是，无论我尝试使用额外的textSprovider，无论如何。这是我的代码

IncrementalValuesProvider<AdditionalText> textFiles = context.AdditionalTextsProvider.Where(static file => file.Path.Contains("appsettings.json")); // tried many things here, like EndsWith(".json") etc..
IncrementalValuesProvider<(string name, string content)> namesAndContents = textFiles.Select((text, cancellationToken) => (name: Path.GetFileNameWithoutExtension(text.Path), content: text.GetText(cancellationToken)!.ToString()));

context.RegisterSourceOutput(namesAndContents, (spc, nameAndContent) =>
    {
         nameAndContent.content; //always empty 
         nameAndContent.name; //always empty 
    });

，当我实现ISOURCEGENERATOR（相同的解决方案，相同项目）时，这一行代码就可以了！

var file = context.AdditionalFiles.FirstOrDefault(x => x.Path.Contains("appsettings.json"));

引用代码生成器的项目：

<Project Sdk="Microsoft.NET.Sdk.Web">
  <PropertyGroup>
    <TargetFramework>net6.0</TargetFramework>
    <Nullable>enable</Nullable>
    <ImplicitUsings>enable</ImplicitUsings>
  </PropertyGroup>
  <ItemGroup>
    <PackageReference Include="Dapper" Version="2.0.123" />
    <PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="6.0.4" />
    <PackageReference Include="Microsoft.EntityFrameworkCore" Version="6.0.3" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="6.0.3" />
    <PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="6.0.3">
      <PrivateAssets>all</PrivateAssets>
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
    </PackageReference>
    <PackageReference Include="Scrutor" Version="4.1.0" />
    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.3.0" />
  </ItemGroup>
  <ItemGroup>
        <ProjectReference Include="..\myproject\myproject.csproj" />
    <ProjectReference Include="..\myproject.EFCore\myproject.EFCore.csproj" OutputItemType="Analyzer" ReferenceOutputAssembly="false" />
  </ItemGroup>

  <ItemGroup>
    <AdditionalFiles Include="appsettings.json" />
  </ItemGroup>

</Project>

代码生成器项目：

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>netstandard2.0</TargetFramework>
    <LangVersion>latest</LangVersion>    
    <GeneratePackageOnBuild>true</GeneratePackageOnBuild> <!-- Generates a package at build -->
    <IncludeBuildOutput>false</IncludeBuildOutput> <!-- Do not include the generator as a lib dependency -->
  </PropertyGroup>
  <ItemGroup>
    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.1.0" PrivateAssets="all" />
    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.3" PrivateAssets="all" />
  </ItemGroup>
  <ItemGroup>
    <!-- Generator dependencies -->
    <PackageReference Include="Newtonsoft.Json" Version="13.0.1" GeneratePathProperty="true" PrivateAssets="all" />
  </ItemGroup>
 <PropertyGroup>   <GetTargetPathDependsOn>$(GetTargetPathDependsOn);GetDependencyTargetPaths</GetTargetPathDependsOn>
  </PropertyGroup>
  <Target Name="GetDependencyTargetPaths">
    <ItemGroup>
      <TargetPathWithTargetPlatformMoniker Include="$(PKGNewtonsoft_Json)\lib\netstandard2.0\Newtonsoft.Json.dll" IncludeRuntimeDependency="false" />
    </ItemGroup>
  </Target>
    <ItemGroup>
    <!-- Package the generator in the analyzer directory of the nuget package -->
    <None Include="$(OutputPath)\$(AssemblyName).dll" Pack="true" PackagePath="analyzers/dotnet/cs" Visible="false" />
    <!-- Package the props file -->
  </ItemGroup>
</Project>

Answer 1

如果将其他文本提供商与汇编相结合，它对我有用（灵感来自此出色的文章）：

public void Initialize(IncrementalGeneratorInitializationContext context)
{
    var files = context.AdditionalTextsProvider
        .Where(a => a.Path.EndsWith("appsettings.json"))
        .Select((a, c) => (Path.GetFileNameWithoutExtension(a.Path), a.GetText(c)!.ToString()));

    var compilationAndFiles = context.CompilationProvider.Combine(files.Collect());
            
    context.RegisterSourceOutput(compilationAndFiles, (productionContext, sourceContext) => Generate(productionContext, sourceContext));
}

void Generate(SourceProductionContext context, (Compilation compilation, ImmutableArray<(string, string)> files) compilationAndFiles)
{
    //emit generated files...
}

更新：

再次通过Visual Studio 17.4进行了测试。与汇编的结合似乎不再是必要的。当AppSettings.json仅使用afrefextsprovider注册时，将以预期的方式调用发电机。

Answer 2

我尝试了复制，但一切都对我有用。

我将源生成器定义为此

namespace ConsoleAppSourceGenerator
{
    [Generator]
    public class TxtGenerator : IIncrementalGenerator
    {
        private static int counter;

        public void Initialize(IncrementalGeneratorInitializationContext initContext)
        {
            IncrementalValuesProvider<AdditionalText> textFiles = initContext.AdditionalTextsProvider
                .Where(static file => file.Path.EndsWith(".txt"));

            IncrementalValuesProvider<(string name, string content)> namesAndContents = textFiles
                .Select((text, cancellationToken) => (name: Path.GetFileNameWithoutExtension(text.Path), content: text.GetText(cancellationToken)!.ToString()));

            initContext.RegisterSourceOutput(namesAndContents, (spc, nameAndContent) =>
            {
                spc.AddSource($"TxtFile.{nameAndContent.name}.g.cs", $@"
// Counter {Interlocked.Increment(ref counter)}
public static partial class TxtFile
{{
    public const string {nameAndContent.name} = ""{nameAndContent.content}"";
}}");
            });
        }
    }
}

和源生成器项目

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

  <PropertyGroup>
    <TargetFramework>netstandard2.0</TargetFramework>
      <Nullable>enable</Nullable>
      <LangVersion>Latest</LangVersion>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.3">
      <PrivateAssets>all</PrivateAssets>
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
    </PackageReference>
    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.1.0" />
  </ItemGroup>
</Project>

，然后在另一个项目中将其定义为foo.txt文件，

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

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net6.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
      <EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
      <CompilerGeneratedFilesOutputPath>Generated</CompilerGeneratedFilesOutputPath>
  </PropertyGroup>

    <ItemGroup>
        <Compile Remove="$(CompilerGeneratedFilesOutputPath)/**/*.cs" />
    </ItemGroup>

  <ItemGroup>
    <ProjectReference Include="..\ConsoleAppSourceGenerator\ConsoleAppSourceGenerator.csproj" OutputItemType="Analyzer" ReferenceOutputAssembly="false" />
  </ItemGroup>
    
    <ItemGroup>
        <AdditionalFiles Include="foo.txt"/>
    </ItemGroup>

</Project>

如果我通过Visual Studio查看依赖项 - ＆gt; Analyzers-- ＆gt; consoleappsourcegenerator＆gt; txtfile.foo.g.cs然后，它正确地增加了我在文件中的每一个更改的计数器（请参见步骤9 ）。

我将生成的文件存储在路径consoleapp/oferated/consoleappsourcegenerator/consoleappsourcegenerator.txtgenerator

您是否记得将[Generator]属性添加到iincrementalgenerator？

您能测试一下并验证这对您不起作用吗？

Answer 3

您的消费项目文件中的“额外文件”是确保这些文件由您的源/增量发电机捕获的关键。

发现使用“＆lt;其他files inculce ='...' /＆gt;”在某些项目中没有必要的源/源/增量加生器的ASPNET核心项目。默认情况下，将.cshtml文件作为其他文件包含。

此外，文件球模式与“ Include”参数一起使用。