dependency-injection

问题 When using dependency injection through a constructor I always need to check for nulls before passing the instance to an internal property. e.g. public UserManager(User user, IStateManager stateManager) { if(user == null) throw new ArgumentNullException; if(statemanager == null) throw new ArgumentNullException("stateManager"); _user = user; _stateManager = statemanager; } repeating this pattern on every controller / class seems repetitive. Is there a better way to handle this? btw different

问题 In an ASP.Net Core application, its easy to configure Autofac using: public class Program { public static void Main(string[] args) { // ASP.NET Core 3.0+: // The UseServiceProviderFactory call attaches the // Autofac provider to the generic hosting mechanism. var host = Host.CreateDefaultBuilder(args) .UseServiceProviderFactory(new AutofacServiceProviderFactory()) .ConfigureWebHostDefaults(webHostBuilder => { webHostBuilder .UseContentRoot(Directory.GetCurrentDirectory()) .UseIISIntegration()

问题 In an ASP.Net Core application, its easy to configure Autofac using: public class Program { public static void Main(string[] args) { // ASP.NET Core 3.0+: // The UseServiceProviderFactory call attaches the // Autofac provider to the generic hosting mechanism. var host = Host.CreateDefaultBuilder(args) .UseServiceProviderFactory(new AutofacServiceProviderFactory()) .ConfigureWebHostDefaults(webHostBuilder => { webHostBuilder .UseContentRoot(Directory.GetCurrentDirectory()) .UseIISIntegration()

问题 In an ASP.Net Core application, its easy to configure Autofac using: public class Program { public static void Main(string[] args) { // ASP.NET Core 3.0+: // The UseServiceProviderFactory call attaches the // Autofac provider to the generic hosting mechanism. var host = Host.CreateDefaultBuilder(args) .UseServiceProviderFactory(new AutofacServiceProviderFactory()) .ConfigureWebHostDefaults(webHostBuilder => { webHostBuilder .UseContentRoot(Directory.GetCurrentDirectory()) .UseIISIntegration()

问题 We need to add configuration providers to the native IConfiguration that is supplied to the Azure Functions natively. Currently we are completely replacing it with our custom Iconfiguration using the following code: public class Startup : FunctionsStartup { public override void Configure(IFunctionsHostBuilder builder) { ... var configuration = new ConfigurationBuilder() .SetBasePath(Directory.GetCurrentDirectory()) .AddAzureKeyVault(...) .AddJsonFile("local.settings.json", true, true)

问题 I am dealing with a WeChat project that post XML message to my server. The message could be any one of several types. Hence I first deserialize the message to corresponding object with a base "WxMessage", and then return the object to a dispatcher, which will find out a correct message handler to handle the message. The handlers, corresponding to each type of messages, were registered to the DependencyInjection of Asp.net core 2.1 with a IWxMessageHandler<> interface. services.AddScoped

问题 Okay, let's make this simple. I have created a simple library called my-network-library with two classes in it. First one is a Hilt module called BaseNetworkModule @Module @InstallIn(ApplicationComponent::class) object BaseNetworkModule { // Client @Singleton @Provides fun provideOkHttpClient(): OkHttpClient { return OkHttpClient.Builder() // my default okhttp setup goes here .build() } } and the second one is a simple class. class MyAwesomeClass { fun doMagic() { // magic code goes here } }

问题 For example I have this class: public class UnitOfWork : IUnitOfWork { private readonly ApplicationDbContext _context; public IProductRepository Products { get; private set; } public ICategoryRepository Categories { get; private set; } public IPhotoRepository Photos { get; private set; } public UnitOfWork(ApplicationDbContext context, IProductRepository productRepository, ICategoryRepository categoryRepository, IPhotoRepository photoRepository) { _context = context; Products =

问题 I have a hard time understanding why the behaviour is different to apply the service locator pattern in the Startup Configure method when using the IApplicationBuilder.ApplicationServices in stead of IServiceProvider . When I use IApplicationBuilder.ApplicationServices (which sets the IServiceProvider that provides access to the application 's service container ) I get the following error: Cannot resolve scoped service '...' from root provider In contrast, when I use the injected

问题 I have a hard time understanding why the behaviour is different to apply the service locator pattern in the Startup Configure method when using the IApplicationBuilder.ApplicationServices in stead of IServiceProvider . When I use IApplicationBuilder.ApplicationServices (which sets the IServiceProvider that provides access to the application 's service container ) I get the following error: Cannot resolve scoped service '...' from root provider In contrast, when I use the injected