ASP.Net运行时核心注册Controller

Question

我问自己是否可以在运行时加载一个包含 Controllers 的 DLL 并使用它。

我找到的唯一解决方案是通过 ApplicationPart 在 StartUp:

上添加程序集

var builder = services.AddMvc();
builder.AddApplicationPart(
    AssemblyLoadContext.Default.LoadFromAssemblyPath(
        @"PATH\ExternalControllers.dll"
));

有谁知道是否可以随时注册 Controller，因为该解决方案的问题是，当您想要添加另一个 DLL 时，您必须重新启动 WebService Controllers 在里面。如果您可以随时添加它们并随时在应用程序中注册它们，那就太好了。

Answer 1

现在这是可能的。

请参阅有关 how to add dynamic controllers 的更新文档：

public class GenericControllerFeatureProvider : IApplicationFeatureProvider<ControllerFeature>
{
    public void PopulateFeature(IEnumerable<ApplicationPart> parts, ControllerFeature feature)
    {
        // This is designed to run after the default ControllerTypeProvider, 
        // so the list of 'real' controllers has already been populated.
        foreach (var entityType in EntityTypes.Types)
        {
            var typeName = entityType.Name + "Controller";
            if (!feature.Controllers.Any(t => t.Name == typeName))
            {
                // There's no 'real' controller for this entity, so add the generic version.
                var controllerType = typeof(GenericController<>)
                    .MakeGenericType(entityType.AsType()).GetTypeInfo();
                feature.Controllers.Add(controllerType);
            }
        }
    }
}

Answer 2

现在可以在 .net core 2.0+

请看代码ActionDescriptorCollectionProvider.cs:

    public ActionDescriptorCollectionProvider(
        IEnumerable<IActionDescriptorProvider> actionDescriptorProviders,
        IEnumerable<IActionDescriptorChangeProvider> actionDescriptorChangeProviders)
    {
        _actionDescriptorProviders = actionDescriptorProviders
            .OrderBy(p => p.Order)
            .ToArray();

        _actionDescriptorChangeProviders = actionDescriptorChangeProviders.ToArray();

        ChangeToken.OnChange(
            GetCompositeChangeToken,
            UpdateCollection);
    }

步骤1:ImplementIActionDescriptorChangeProviderclass:

public class MyActionDescriptorChangeProvider : IActionDescriptorChangeProvider
{
    public static MyActionDescriptorChangeProvider Instance { get; } = new MyActionDescriptorChangeProvider();

    public CancellationTokenSource TokenSource { get; private set; }

    public bool HasChanged { get; set; }

    public IChangeToken GetChangeToken()
    {
        TokenSource = new CancellationTokenSource();
        return new CancellationChangeToken(TokenSource.Token);
    }
}

2:AddSingleton Startup.ConfigureServices() 步：

public void ConfigureServices(IServiceCollection services)
{
    services.AddMvc();
    services.AddSingleton<IActionDescriptorChangeProvider>(MyActionDescriptorChangeProvider.Instance);
    services.AddSingleton(MyActionDescriptorChangeProvider.Instance);
}

第 3 步：在运行时注册控制器：

public class TestController : Controller
{
    private readonly ApplicationPartManager _partManager;
    private readonly IHostingEnvironment _hostingEnvironment;
    public TestController(
        ApplicationPartManager partManager,
        IHostingEnvironment env)
    {
        _partManager = partManager;
        _hostingEnvironment = env;
    }
    public IActionResult RegisterControllerAtRuntime()
    {
        string assemblyPath = @"PATH\ExternalControllers.dll";
        var assembly = AssemblyLoadContext.Default.LoadFromAssemblyPath(assemblyPath);
        if (assembly != null)
        {
            _partManager.ApplicationParts.Add(new AssemblyPart(assembly));
            // Notify change
            MyActionDescriptorChangeProvider.Instance.HasChanged = true;
            MyActionDescriptorChangeProvider.Instance.TokenSource.Cancel();
            return Content("1");
        }
        return Content("0");
    }
}

ASP.Net运行时核心注册Controller

ASP.Net Core register Controller at runtime

.net

c#

.net-assembly

asp.net-core-mvc

asp.net-core