"<var>X</var>" является типом коллекции и не может быть сериализован при назначении типу интерфейса, не реализующему интерфейс IEnumerable ("<var>Y</var>").

Message in Russian (Русский)

Unlocalized message

'<var>X</var>' is a collection type and cannot be serialized when assigned to an interface type that does not implement IEnumerable ('<var>Y</var>'.)

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