Dependency Injection from Multiple Assemblies using Structuremap

Question

I am new to DI concept and new to structuremap. I am trying to full fill a scenario where all my interfaces are in AssemblyA and all my implementations are in AssemblyB. I want to use Structuremap to inject instance of AssemblyB class in constructor which has dependency on interface from AssemblyA

public class Customer(ICustomerService)
{

}

ICustomerService is in AssemblyA and CustomerService class is in assemblyB. I want Structuremap to inject CustomerService instance in this constructor. I am assuming that if the name of class is same as the name of interface prefixed with and I. Structuremap will recognize it automatically.

I have written the following configuration.

 x =>
        {


            x.Scan(scan =>
                {
                    scan.Assembly("AssemblyA");
                    scan.Assembly("AssemblyB");
                    scan.TheCallingAssembly();
                    scan.WithDefaultConventions();
            });

but it gives me error

StructureMap Exception Code:  202
No Default Instance defined for PluginFamily AssemblyA.ICustomerService, AssemblyA, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null

I want to use the default conventions and avoid registering each interface to a class.

Afraz Ali Afraz Ali · Accepted Answer · 2013-01-04T11:44:57

Ok, I got it to work but I am even more confused now.

This code seems to work

IContainer container = new Container(c =>
            {
                c.Scan(x =>
                {
                    x.Assembly("AssemblyA");
                    x.Assembly("AssemblyB");
                    x.IncludeNamespace("AssemblyA");
                    x.TheCallingAssembly();
                    x.WithDefaultConventions();
                });
            });

Here I have simple added x.IncludeNamespace("AssemblyA"); after the AssemblyB scan thinking that it needs this namespace and it has started working.

My problem is solved but I don't know what was wrong or if this is the right way to go. Any help will still be greatly appreciated.

Dependency Injection from Multiple Assemblies using Structuremap

1 Answers