Convert dictionary to list collection in C#

c# list dictionary
Edy Cu picture Edy Cu · Oct 19, 2010 · Viewed 215.1k times · Source

I have a problem when trying to convert a dictionary to list.

Example if I have a dictionary with template string as key and string as value. Then I wish to convert the dictionary key to list collection as a string.

Dictionary<string, string> dicNumber = new Dictionary<string, string>();
List<string> listNumber = new List<string>();

dicNumber.Add("1", "First");
dicNumber.Add("2", "Second");
dicNumber.Add("3", "Third");

// So the code may something look like this
//listNumber = dicNumber.Select(??????);

Answer

Justin Niessner picture Justin Niessner · Oct 19, 2010

To convert the Keys to a List of their own:

listNumber = dicNumber.Select(kvp => kvp.Key).ToList();

Or you can shorten it up and not even bother using select:

listNumber = dicNumber.Keys.ToList();

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