How to specify named instance as constructor parameter for type that are auto-registered for StructureMap

Question

Using StructureMap, We have all types that are auto registered.

public class MessageRegistry : Registry
{
    public MessageRegistry(){
        Scan(x =>
             {
                 x.AssemblyContainingType(typeof (FormatHelper));
                 x.ConnectImplementationsToTypesClosing(typeof (IMessage<>));
             });
    }
}

So, in case we look for IMessage<Currency>, it will find below type:

CurrencyMessageHandler : IMessage<Currency>
{
    public CurrencyMessageHandler(ISession instance) 
}

As to the constructor parameter type ISession, we like it to be auto wired, however, we have got more than 1 implementation like SqlSession and OracleSession. In this case, we would like to pass SqlSession as constructor parameter.

How to specify named instance as constructor parameter in this case?

Much appreciated.

Answer 1

I had this same exact problem and I solved it by excluding the type from the scan and then custom configuring it:

Scan(scan => scan.Exclude(t => t == typeof(CurrencyMessageHandler));

and then:

For<IMessage<Currency>>.Add<CurrencyMessageHandler>()
     .Ctor<ISession>.Is(a => a.TheInstanceNamed("SqlServer"));