Get grouped comma separated values with linq

    var dCounts =
        (from i in dic
            group i by i.Value into g
            select new { g.Key, count = g.Count(), Items = string.Join(",", g.Select(kvp => kvp.Key)) });

Use string.Join(",", {array}), passing in your array of keys.

You can use:

var dCounts = 
    from i in dic 
    group i by i.Value into g 
    select new { g.Key, Count = g.Count(), Values = g }; 

The result created by grouping (value g) has a property Key that gives you the key, but it also implements IEnumerable<T> that allows you to access individual values in the group. If you return just g then you can iterate over all values using foreach or process them using LINQ.

Here is a simple dump function to demonstrate this:

foreach(var el in dCounts) {
  Console.Write(" - {0}, count: {1}, values:", el.Key, el.Count);
  foreach(var item in el.Values) Console.Write("{0}, ", item);
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