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c#using-directives

Aliasing a generic interface with a using alias directive

I am aware that it's not possible to alias a generic type (e.g. using Foo = Dictionary; is invalid), but that the generic type on the right must be closed (e.g. using Foo = Dictionary<int, string>; will work).

However, it seems like it's invalid to alias an IDictionary<string, object>--instead, the alias must be for just the interface IDictionary. The error I get is "CS0308: The non-generic type 'IDictionary' cannot be used with type arguments." Is there a way to alias this entire thing? (Or a better way to achieve what I want?)

A common thing I do in my API is for functions to take an IDictionary<string, object>, and I'd like to do something akin to using ParsedObjects = IDictionary<string, object>;. In fact, I'd like to be able to declare:

using ParsedObjectsHandler = Func<Interaction, object, IDictionary<string, object>, Task>;

(But I am willing to settle for just the former.)

Solution

  • Edit: Although the below answer solves the question (and I'm leaving it up as I could not find the info anywhere else), I did go with V.Lion's suggestion in the comments to define my own delegate type instead.

    The issue was that I was attempting to use System.Collections.IDictionary instead of System.Collections.Generic.IDictionary<TKey, TValue>. Using the latter worked just fine, i.e.:

    using ParsedObjects = System.Collections.Generic.IDictionary<string, object>;