How to transform a Dictionary<object, string> to a Dictionary<object, List<string>> with LINQ

Question

I have two methods that do the same thing, one works with a Dictionary<object, List<string>> and another one with a Dictionary<object, string> doing the same thing but iterating or not the list.

I want to reduce code duplication making just a method that works with Dictionary<object, List<string>> and transforming the Dictionary<object, string> to a Dictionary<object, List<string>> with a list with only one string.

How can I do the transform preferentially with LINQ?

Thanks in advance.

Answer 1

Well you can't cast the dictionary that way, but you could use:

var newDictionary = oldDictionary.ToDictionary(
                                       pair => pair.Key,
                                       pair => new List<string> { pair.Value });

Answer 2

var newDict = oldDict.ToDictionary(x => x.Key, x => new List<string> { x.Value });