未定义类型'集合'vb BC30002

Question

I am attempting to migrate a legacy vb.net application to .net standard and turn it into a nuget package. A good amount of it has been straight forward. I am currently hung up on this error caused by functions like this.

 Public Property ErrorMessages As Collection
        Get
            ErrorMessages = _errorMessages
        End Get
        Set(value As Collection)
            _errorMessages = value
        End Set
    End Property

If i import System.Collections.ObjectModelCollection(Of T) it is asking me for a type and i am unsure how to proceed. It turns my code into Collection(Of,) and expects a second argument. Has anyone faced this before? Do i use a different import statement or how is this dealt with in vb now?

Answer 1

You should almost certainly replace Collection with Dictionary(Of TKey, TValue) , using the dictionary type from the System.Collections.Generic namespace.

Once again, this requires you to fill in the genetic type arguments TKey and TValue with the actual types. You need to figure out from context which type fits the collection. The value of TKey is probably String since that's the only key type VB6' collections properly support. And given the name ( ErrorMessages ), TValue is probably String as well.