What is an IServiceProvider?
The IServiceProvider is responsible for resolving instances of types at runtime, as required by the application. These instances can be injected into other services resolved from the same dependency injection container. The ServiceProvider ensures that resolved services live for the expected lifetime.
How do I get IServiceProvider?
An instance of IServiceProvider itself can be obtained by calling a BuildServiceProvider method of an IServiceCollection. IServiceCollection is a parameter of ConfigureServices method in a Startup class. It seems to be magically called with an instance of IServiceCollection by the framework.
Can I inject IServiceProvider?
You can inject an instance of type IServiceProvider into any method of a class. You can also take advantage of the ApplicationServices property of the IApplicationBuilder interface and the RequestServices property of the HttpContext class to retrieve an IServiceProvider instance.
Is IServiceProvider a singleton?
The ASP.NET Core DI container has a root IServiceProvider which is used to resolve singleton services. For scoped services, the container must first create a new scope, and each scope will have it’s own IServiceProvider .
What is the difference between GetService and GetRequiredService?
The difference is that GetService() returns null if it can’t find the service. GetRequiredService() throws an InvalidOperationException instead.
What is .NET container?
A container is a runnable instance of an image. As you build your image, you deploy your application and dependencies. Then, multiple containers can be instantiated, each isolated from one another. Each container instance has its own filesystem, memory, and network interface.
What are the benefits of dependency injection?
Dependency Injection Benefits
- Reduced Dependencies.
- Reduced Dependency Carrying.
- More Reusable Code.
- More Testable Code.
- More Readable Code.
What is scoped service?
In a scoped service, with every HTTP request, we get a new instance. However, within the same HTTP request, if the service is required in multiple places, like in the view and in the controller, then the same instance is provided for the entire scope of that HTTP request.
Is Iserviceprovider thread-safe?
You can see services factories are stored in ConcurrentDictionary and building an expression for creating service object is executed in separate thread except the first one. And I am sure this expression is also thread-safe (likely stateless). So the default ServiceProvider is thread-safe.
Should every dependency be injected?
Dependency injection is a powerful technique that can be applied in many situations across all layers of an application. But this does not mean that dependency injection should be used every time a class depends on another class.
What is middleware in ASP.NET Core?
A middleware is nothing but a component (class) which is executed on every request in ASP.NET Core application. In the classic ASP.NET, HttpHandlers and HttpModules were part of request pipeline. Middleware is similar to HttpHandlers and HttpModules where both needs to be configured and executed in each request.
Is IServiceProvider thread-safe?
What is IServiceCollection in .NET core?
AddScoped(IServiceCollection, Type, Type) Adds a scoped service of the type specified in serviceType with an implementation of the type specified in implementationType to the specified IServiceCollection.
What is container MVC?
For those who are new to the terms container and Docker, A container image is a lightweight, stand-alone, executable package of a piece of software that includes everything needed to run it: code, runtime, system tools, system libraries, settings.
How do you use a scoped service?
To use scoped services within a BackgroundService , create a scope. No scope is created for a hosted service by default. The scoped background service contains the background task’s logic. The preceding interface defines a single DoWorkAsync method.
What is a singleton service?
A singleton service is a service for which only one instance exists in an application. For a sample application using the app-wide singleton service that this page describes, see the live example / download example showcasing all the documented features of NgModules.
What is a transient service?
With a transient service, a new instance is provided every time an instance is requested whether it is in the scope of same http request or across different http requests. With a scoped service we get the same instance within the scope of a given http request but a new instance across different http requests.