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    copied!<p>You should use constructor injection instead of property injection if possible. This is a better technique, which is recommended by Mark Seeman, because makes dependencies required for object construction explicit and object signature via constructor is more expressive. Code should look like this:</p> <pre><code> abstract class A { public IDependency Dependency { get; private set; } public A (IDependency dependency) { Dependency = dependency; } } class B : A { public B (IDependency dependency) : base(dependency) { } } class C : A { public C (IDependency dependency) : base(dependency) { } } interface IDependency { } class EmptyDependency : IDependency { } class ConcreteDependency : IDependency { } </code></pre> <p>Configuration will be the same as in you example. The following test passes</p> <pre><code> [Test] public void TestSpecificBindingToObjectB() { var kernel = new StandardKernel(new TestModule()); var b = kernel.Get&lt;B&gt;(); var c = kernel.Get&lt;C&gt;(); Assert.AreNotEqual(b.Dependency.GetType(), c.Dependency.GetType()); Assert.AreEqual(typeof(ConcreteDependency), b.Dependency.GetType()); } </code></pre> <p>If you have an optional dependency with default implementation and you are ok with decorating your classes with <code>Inject</code> attribute, you can can pull parent information from request, like this:</p> <pre><code>class TestModule : NinjectModule { public override void Load() { Bind&lt;IDependency&gt;().To&lt;EmptyDependency&gt;(); Bind&lt;IDependency&gt;().To&lt;ConcreteDependency&gt;().When(req =&gt;req.ParentContext.Request.Service == typeof(B)); } } </code></pre> <p>Then the same test given above passes for your class hierarchy with property injection.</p>
 

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