Is there a way to flatten a .Net ILookup into a List?

Question

Is there a quick way to get a flattened List<TElement> from an ILookup<TKey, TElement> that was created from the IEnumerable<TElement> extension?

Updated with example

List<int> list = new List<int>();
var lookup = list.ToLookup(key => key);
list = lookup.?? // How to convert the lookup back to the list

score 31 · Accepted Answer · answered Mar 04 '10 at 16:21

31

lookup.SelectMany( x => x ).ToList()

The transformation to ILookup and back again will have most likely changed the order, however.

answered Mar 04 '10 at 16:21

Tinister

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Asad · Answer 2 · 2010-02-24T03:11:31.877

0

Not sure if this is what you are after. For Dictionary<> to List<>

List<TElement> list iLookUp.Values.ToList<TElement>();

from List<> to Dictionary<>

var dict = list.Cast<TElement>().ToDictionary(t => t.Id, t => t.Description);

edited Feb 24 '10 at 03:11

answered Feb 24 '10 at 03:04

Asad

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Thanks, not quite what I am looking for though. I have updated the question for clarity – Joomala Feb 24 '10 at 03:22
It does not look like `ILookup` has a `Values` property. – Timo Jun 10 '16 at 11:27

Is there a way to flatten a .Net ILookup into a List?

2 Answers2