TL;DR;
It isn’t long, since i struggle to find out how to access DI registered classes in MVC using autofac, and I failed every time, with every phrase.
So, two days ago, I though to myself, let create access point, and it worked. cool, right?
The way i gonna show you, is not officially provided by those who right Autofac, It’s Cheat, a Trick, but it works. Isn’t that enough? Maybe not; so in case you found a better solution feel free to share it with me.
Other solutions:
I list some of the solutions in my mind, that did not worked for me:
- Create new Container:
This solution wasn’t good for me, because i had to register many stuff again and again, also changin one Mapping, require you to remember it and change it in all other containers too. - Using
Resolve,GetServiceor other similar functionalities:
Why this doesn’t work for me, I’m not sure, it look what i wanted to do, but just as i said, unfortunattely, it didn’t worked for me, if it works for you, Thats Great.
Here’s sample of resolvevar builder = new ContainerBuilder(); builder.RegisterType<MyComponent>().As<IService>(); var container = builder.Build(); // Later... using(var scope = container.BeginLifetimeScope()) { var service = scope.Resolve<IService>(); }
My Way, The Cheat
The only way rest for me, was to keep a pointer to the container, so I had to option, some static class, somewhere or a Singleton. I did it with a singleton. I made this class not only for Autofac, but for any unpredictable issue that may come later.
Here’s my Singleton:
using System.Diagnostics.CodeAnalysis;
using Autofac;
namespace MyProject
{
public class GlobalObjects
{
#region Singleton
private static readonly GlobalObjects Instance = null;
static GlobalObjects()
{
Instance = new GlobalObjects();
}
private GlobalObjects()
{
}
public static GlobalObjects GetInstance()
{
return Instance;
}
#endregion
[SuppressMessage("ReSharper", "IdentifierTypo")] //if you are not using Resharper, you can remove these attributes.
public IContainer AutofacContainer { private set; get; }
[SuppressMessage("ReSharper", "IdentifierTypo")]
public GlobalObjects SetAutofacContainer(IContainer container)
{
AutofacContainer = container;
return Instance;
}
}
}
Then i had to pass the Autofac Container reference to my SetAutofacContainer Method of GlobalObjects class.
So i did it after registering the container in Startup.cs file.
...
namespace Judgel.Web
{
public class Startup
{
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public IConfiguration Configuration { get; }
public IServiceProvider ConfigureServices(IServiceCollection services)
{
...
var builder = new ContainerBuilder();
var dependencyRegistrar = new DependencyRegistrar();
dependencyRegistrar.Register(builder);
builder.RegisterType<LayoutService>().As<LayoutService>().InstancePerLifetimeScope();
builder.Populate(services);
var container = builder.Build();
GlobalObjects.GetInstance().SetAutofacContainer(container);
return container.Resolve<IServiceProvider>();
}
...
}
}
In the end, you can access it any where, for example i need it in my view, so i call it like this:
@{
var di = GlobalObjects.GetInstance().AutofacContainer;
LayoutService layoutService = di.Resolve<LayoutService>();
var userId = Context.User.GetUserId();
Person person = layoutService.GetPerson(userId); //model
ApplicationUser user= layoutService.GetUser(userId);
}
<!DOCTYPE html>
<html lang="en" class="loading">
...
</html>
The first line is what you need, that’s how we access the Autofac Container.
The second line, is what I use, to resolve my desired object.
After that, i just use my object in my desired way, and it will be different in your scenario .
Thank you for reading,
Hassan Faghihi.