Castle Windsor: Setting a parameter value to an empty string.

Question

How can I allow one of my string parameters to be an empty string?

I get this error when I try either nothing or a single space (names changed):

Could not resolve non-optional dependency for 'test.User' (MyNamespace.MyObject). Parameter 'userName' type 'System.String'

Answer 1

container.Register(
   Component.For<Foo>()
      .DependsOn(new
      {
         someString = string.Empty
      }));

but first of all, why do you want to set that dependency to empty string? It does feel like hacking to me.

Answer 2

Turns out it's much easier, and likely more correct, to add a constructor that doesn't take the parameter(s) you want to leave blank.

Answer 3

What if there is already a default value, which is null, or some other non-empty string? One solution is to create a component:

<component id="emptyString" type="System.String, mscorlib" />

and then use it in your parameters node:

<parameters> <someStringParameter>${emptyString}</someStringParameter> </parameters>

But it seems like there ought to be a simpler way.