CODEWITHSUNDEEP
asp.net-mvcdependency-injectionninject
dknaack
dknaack

Reputation: 60466

Ninject Problem getting instances

i got the tiny interface ITest:

public interface ITest
{
    void DoSomething();
}

and some implementations of ITest

public class Test : ITest
{
    public void DoSomething()
    {
        throw new NotImplementedException();
    }
}

public class Test2 : ITest
{
    public void DoSomething()
    {
        throw new NotImplementedException();
    }
}

public class Test3 : ITest
{
    public void DoSomething()
    {
        throw new NotImplementedException();
    }
}

public class Test4 : ITest
{
    public void DoSomething()
    {
        throw new NotImplementedException();
    }
}

Now i setting up Ninject:

kernel.Bind<ITest>().To<Test>().Named("Test");
kernel.Bind<ITest>().To<Test2>().Named("Test");
kernel.Bind<ITest>().To<Test3>().Named("Test");
kernel.Bind<ITest>().To<Test4>().Named("Test");

And here is my first Problem.

If iam trying to get an instance using

ITest test = kernel.Get<ITest>("Test");

it results in a exception "Error activating ITest More than one matching bindings are available. ...". The documentation says: "Gets an instance of the specified service by using the first binding with the specified name."

Second Problem:

List<ITest> servicesList = new List<ITest>(kernel.GetAll<ITest>("Test"));

results in a exception "Error activating string No matching bindings are available, and the type is not self-bindable. ...". The documentation says: "Gets all instances of the specified service using bindings registered with the specified name."

Any ideas ? Thanks in advance!

Upvotes: 2

Views: 1923

Answers (1)

Darin Dimitrov
Darin Dimitrov

Reputation: 1038810

You are giving all your instances the same name Test so it's normal that this would be ambiguous. Give them different names when registering your kernel:

kernel.Bind<ITest>().To<Test>().Named("Test1");
kernel.Bind<ITest>().To<Test2>().Named("Test2");
kernel.Bind<ITest>().To<Test3>().Named("Test3");
kernel.Bind<ITest>().To<Test4>().Named("Test4");

Now you can fetch your instances by name:

ITest test = kernel.Get<ITest>("Test3");

And to get them all you no longer need a name:

List<ITest> servicesList = kernel.GetAll<ITest>().ToList();

Upvotes: 4

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