Remnant.Dependency.Injector 2.0.0

Remnant Dependency Injector

• Install nuget package:

    Install-Package Remnant.Dependency.Injector -Version 2.0.0
  

• The injection follows a pull pattern unlike all other DI containers which uses a push pattern

• The pull pattern has no need to declare constructor arguments for DI, also no hierarchical DI wiring is required

• The DI container is global accessible within your current app domain

• Anywhere, any place in your code the DI container can be requested to resolve the object needed

• An extension method 'Resolve<<TType>>' is implemented on 'object' to allow any objects to call the container

• You can use the [Inject] attribute on fields which will automatically inject the dependency object

Note: When using the [Inject] attribute to decorate class fields, your class must be specified as partial.

Important: If your class already contains an empty parameter constructor: <br/>

• The analyzer can't generate a constructor with the injection code because the method (constructor) exists already
• In that case the Analyzer generates a public 'Inject' method, as well as a static 'Create' method on the class
• So you can call the static 'Create' method which will create an instance of the class and it calls the 'Inject' method to perform the injection
• Or you can instantiate the class and call the 'Inject' method yourself
• Keep in mind on your constructor, the injected fields will be null (unless you call 'Inject()' as the first thing on your constructor)
• Ensure that the specified injected fields are not <b>readonly</b>
• <i>(see example 4)</i>.

Quick console app examples (<a href="https://learn.microsoft.com/en-us/dotnet/csharp/fundamentals/program-structure/top-level-statements">using top-level statements feature</a>):

Example 1: register something with the container (used by all examples)

using ConsoleApp;
using Remnant.Dependency.Injector;

DIContainer
  .Create("MyContainer")
  .Register(new List<string> { "John", "Jane" }, "Names");

Example 2: using extension method 'Resolve' on object

new object()
  .Resolve<List<string>>("Names")
  .ForEach(name => Console.WriteLine(name));
}

Example 3: using 'Inject' attribute

new Members().ListNames();

// Members.cs
using Remnant.Dependency.Injector;

namespace ConsoleApp
{
  public partial class Members
  {
    [Inject("Names")]
    private readonly List<string> _names;
    public void ListNames() => _names.ForEach(name => Console.WriteLine(name));
  }
}

Example 4: using static 'Create' method

//... static 'Create' member is generated which will do injection
Members.Create().ListNames();

// Members.cs
using Remnant.Dependency.Injector;

namespace ConsoleApp
{
  public partial class Members
  {
    [Inject("Names")]
    private List<string> _names; //must not be readonly

    public Members()
    {
      Console.WriteLine("Remnant code analyzer can not generate a constructor for injection, thus use generated static 'Create' member.");
    }

    public void ListNames() => _names.ForEach(name => Console.WriteLine(name));
  }
}