c# - PostBuild 事件中的 .NET Core Assembly.LoadFile

Question

我需要在构建后从我的一些 C# 类生成 typescript 文件。

我创建了 dotnet cli 工具 并添加了构建后事件

dotnet tsgenerator "$(TargetPath)"

其中 $(TargetPath) 是指向的宏，例如 D:\Test\bin\Release\netcoreapp2.0\my.dll

接下来，我尝试用下一种方式加载程序集:

public static void Main(string[] args)
{
    var dllPath = args[0]; // "D:\Test\bin\Release\netcoreapp2.0\my.dll"
    var assembly = Assembly.LoadFile(dllPath);
    var types = assembly.GetExportedTypes(); // Throws exception
}

但是我得到了 ReflectionTypeLoadException 说 Could not load file or assembly for some references assemblies (for example, Microsoft.AspNetCore.Antiforgery) .

我如何为 .NET Core 应用程序加载程序集？

Answer 1

我在 github issue 找到了解决方案. amits1995留言和 angelcalvasp .

我已添加 <CopyLocalLockFileAssemblies>true</CopyLocalLockFileAssemblies>到我的 csproj 并使用此代码加载程序集:

public static class AssemblyLoader
{
    public static Assembly LoadFromAssemblyPath(string assemblyFullPath)
    {
        var fileNameWithOutExtension = Path.GetFileNameWithoutExtension(assemblyFullPath);
        var fileName = Path.GetFileName(assemblyFullPath);
        var directory = Path.GetDirectoryName(assemblyFullPath);

        var inCompileLibraries = DependencyContext.Default.CompileLibraries.Any(l => l.Name.Equals(fileNameWithOutExtension, StringComparison.OrdinalIgnoreCase));
        var inRuntimeLibraries = DependencyContext.Default.RuntimeLibraries.Any(l => l.Name.Equals(fileNameWithOutExtension, StringComparison.OrdinalIgnoreCase));

        var assembly = (inCompileLibraries || inRuntimeLibraries)
            ? Assembly.Load(new AssemblyName(fileNameWithOutExtension))
            : AssemblyLoadContext.Default.LoadFromAssemblyPath(assemblyFullPath);

        if (assembly != null)
            LoadReferencedAssemblies(assembly, fileName, directory);

        return assembly;
    }

    private static void LoadReferencedAssemblies(Assembly assembly, string fileName, string directory)
    {
        var filesInDirectory = Directory.GetFiles(directory).Where(x => x != fileName).Select(x => Path.GetFileNameWithoutExtension(x)).ToList();
        var references = assembly.GetReferencedAssemblies();

        foreach (var reference in references)
        {
            if (filesInDirectory.Contains(reference.Name))
            {
                var loadFileName = reference.Name + ".dll";
                var path = Path.Combine(directory, loadFileName);
                var loadedAssembly = AssemblyLoadContext.Default.LoadFromAssemblyPath(path);
                if (loadedAssembly != null)
                    LoadReferencedAssemblies(loadedAssembly, loadFileName, directory);
            }
        }
    }
}

用法:

public static void Main(string[] args)
{
    var dllPath = args[0]; // "D:\Test\bin\Release\netcoreapp2.0\my.dll"
    var assembly = AssemblyLoader.LoadFromAssemblyPath(dllPath);
    var types = assembly.GetExportedTypes(); // No exceptions
}