c# - 对于动态加载的 Razor 类库，ASP.NET Core 运行时编译失败并显示 "Cannot find compilation library location for package"

Question

我正在使用以下代码将 Razor 类库动态加载到我的 ASP.NET Core 3.0 中应用程序:

var pluginAssembly = AssemblyLoadContext.Default.LoadFromAssemblyPath(file.FullName);
var partFactory = ApplicationPartFactory.GetApplicationPartFactory(pluginAssembly);
foreach (var part in partFactory.GetApplicationParts(pluginAssembly))
    MvcBuilder.PartManager.ApplicationParts.Add(part);

var relatedAssemblies = RelatedAssemblyAttribute.GetRelatedAssemblies(pluginAssembly, throwOnError: true);
foreach (var assembly in relatedAssemblies)
{
    partFactory = ApplicationPartFactory.GetApplicationPartFactory(assembly);
    foreach (var part in partFactory.GetApplicationParts(assembly))
        MvcBuilder.PartManager.ApplicationParts.Add(part);
}

这工作正常， Controller 和 View 最初正在工作。但是如果我还添加了 Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation包和以下到 Startup.cs :

services.Configure<MvcRazorRuntimeCompilationOptions>(options =>
    {
        options.FileProviders.Add(new PhysicalFileProvider(Path.Combine(WebHostEnvironment.ContentRootPath, "..\\AppPlugin")));
    });

我一编辑 *.cshtml 就会收到以下异常-文件:

InvalidOperationException: Cannot find compilation library location for package 'AppPlugin'

• Microsoft.Extensions.DependencyModel.CompilationLibrary.ResolveReferencePaths(ICompilationAssemblyResolver resolver, List assemblies)

• Microsoft.Extensions.DependencyModel.CompilationLibrary.ResolveReferencePaths()

• Microsoft.AspNetCore.Mvc.ApplicationParts.AssemblyPartExtensions+<>c.b__0_0(CompilationLibrary library)

• System.Linq.Enumerable+SelectManySingleSelectorIterator.MoveNext()
• System.Collections.Generic.List.InsertRange(int index, IEnumerable collection)

• Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation.RazorReferenceManager.GetReferencePaths()

• Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation.RazorReferenceManager.GetCompilationReferences()

我还需要加载其他东西才能让它工作吗？
如果我从 FileProviders 中省略插件路径运行时编译适用于“非插件 View ”。

Answer 1

通过使用 razor 类库的以下项目设置，我能够使其工作。关键是将 PreserveCompilationContext 设置为 false。

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

  <PropertyGroup>
    <TargetFramework>netcoreapp3.1</TargetFramework>
    <AddRazorSupportForMvc>true</AddRazorSupportForMvc>
    <PreserveCompilationContext>false</PreserveCompilationContext>
  </PropertyGroup>

  <ItemGroup>
    <FrameworkReference Include="Microsoft.AspNetCore.App" />
  </ItemGroup>
</Project>

除此之外，您还必须添加对主插件程序集和 View 中使用的任何其他程序集的引用。

services.Configure<MvcRazorRuntimeCompilationOptions>(options =>
{
    options.FileProviders.Add(new PhysicalFileProvider(Path.Combine(WebHostEnvironment.ContentRootPath, "..\\AppPlugin")));
    opts.AdditionalReferencePaths.Add(pluginAssembly.Location);
});