c# 4.0 - Possible to register NullObject implementation as a fallback for a generic interface? -

we use lot of generics in our code. example icommandhandler<t> t icommand, icommandvalidator<t> etc etc

not has icommandvalidator implementation. looking use nullobject pattern provide fall option avoid having test if validator null.

for example

public class nullobjectcommandvalidator : icommandvalidator<icommand> {     public bool isvalid(icommand command)     {         return true;     } } 

we register like:

    builder.registerassemblytypes(assemblies)         .asclosedtypesof(typeof(icommandvalidator<>))         .instanceperhttprequest(); 

i hoping able register nullobjectcommandvalidator default icommandvalidator didn't have concrete implementation using process registering other icommandvalidators<> , registering null version @ end , preserving existing defaults.

is possible?

you should change nullobjectcommandvalidator generic type nullobjectcommandvalidator<tcommand>. way can register follows:

builder.registergeneric(typeof(nullobjectcommandvalidator<>))     .as(typeof(icommandvalidator<>)); 

nullobjectcommandvalidator<tcommand> looks this:

public class nullobjectcommandvalidator<tcommand> : icommandvalidator<tcommand> {     public bool isvalid(tcommand command)     {         return true;     } }