如何在 Startup.cs 中以数组形式获取 .NET 8.0 项目的所有项目引用

Question

我有一个 ASP.NET 后端项目，其中包含几个小型类库项目作为参考。

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

  <PropertyGroup>
    <TargetFramework>net8.0</TargetFramework>
    <Nullable>enable</Nullable>
    <ImplicitUsings>enable</ImplicitUsings>
    <DockerDefaultTargetOS>Linux</DockerDefaultTargetOS>
    <DockerComposeProjectPath>..\docker-compose.dcproj</DockerComposeProjectPath>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.VisualStudio.Azure.Containers.Tools.Targets" Version="1.21.0" />
  </ItemGroup>

  <ItemGroup>
    <ProjectReference Include="..\src\Background\Publisher\Publisher.csproj" />
    <ProjectReference Include="..\src\Common\Common.csproj" />
    <ProjectReference Include="..\src\Data\Data.csproj" />
    <ProjectReference Include="..\src\Identity\Identity.csproj" />
    <ProjectReference Include="..\src\Transaction\Transaction.csproj" />
  </ItemGroup>

</Project>

我打算在

ConfigureServices

方法中使用汇编来注册这些类库中定义的所有服务：

public static void ConfigureServices(this IServiceCollection services)
{
    // TODO: Get all project references as an array to optimize below code.
    var serviceTypes = Assembly.GetExecutingAssembly().GetTypes();
    var idTypes = Assembly.Load("Identity").GetTypes();
    var txTypes = Assembly.Load("Transaction").GetTypes();

    serviceTypes = serviceTypes.Concat(idTypes).Concat(txTypes).ToArray()
                   .Where(t => typeof(IService).IsAssignableFrom(t)
                               && !t.IsInterface && !t.IsAbstract)
                   .ToArray();

    foreach (var serviceType in serviceTypes)
    {
        var interfaceType = serviceType.GetInterfaces()
                                       .FirstOrDefault(i => typeof(IService).IsAssignableFrom(i));

        if (interfaceType != null)
        {
             services.AddScoped(interfaceType, serviceType);
        }
    }
}

以下是我正在使用的一些示例服务。

// Common library
public interface IService
{
}

// Identity library
public interface IUserService : IService 
{
}

public class UserService : IUserService 
{
}

// Transaction library
public interface ITransactionService : IService 
{
}

public class TransactionService : ITransactionService 
{
}

是否可以在

ConfigureServices

的

Startup

方法中以数组形式检索所有引用的库项目？

Answer 1

您可以使用

 Assembly.GetExecutingAssembly();

获取当前程序集，然后使用 IService 接口查询加载的程序集并将它们添加到作用域服务中。

更多详情，您可以参考下面的例子：

var currentAssembly = Assembly.GetExecutingAssembly();
 
 var referencedAssemblies = currentAssembly.GetReferencedAssemblies()
                                          .Select(Assembly.Load)
                                          .ToList();

 referencedAssemblies.Add(currentAssembly);

 var serviceTypes = referencedAssemblies
    .SelectMany(assembly => assembly.GetTypes())
    .Where(type => typeof(IService).IsAssignableFrom(type) &&
                   !type.IsInterface &&
                   !type.IsAbstract)
    .ToList();

foreach (var serviceType in serviceTypes)
{
    var interfaceType = serviceType.GetInterfaces()
        .FirstOrDefault(i => typeof(IService).IsAssignableFrom(i));

    if (interfaceType != null)
    {
        builder.Services.AddScoped(interfaceType, serviceType);
    }
}

结果：