Linq lambda expression to get at least one duplicate along with non duplicates

Question

I have a list:

List<Dev> devices= new List<Dev>(){
    new Dev{ Add="5",Name="A" },
    new Dev{ Add="5",Name="a" },
    new Dev{ Add="9",Name="b" },
    new Dev{ Add="6",Name="c" },
    new Dev{ Add="9",Name="b" },

};

I want to write a Linq "Lambda Expression" which return the records that are not duplicates and also the first record from duplicates based on "Name" in the list. Also ignore case while finding duplicates

Expected Output:

Add=5, Name=A
Add=9, Name=b
Add=6, Name=c

Query what I have now (It returns the "Name" which is duplicate):

results.GroupBy(x => x.Name, StringComparer.OrdinalIgnoreCase)
                                  .Where(g => g.Count() > 1)
                                  .Select(g => g.Key)
                                  .ToList();    

Answer 1

You are pretty close: rather than picking g.Key, pick g.First(), and remove filtering by count:

var list = results.GroupBy(x => x.Name, StringComparer.OrdinalIgnoreCase)
                  .Select(g => g.First())
                  .ToList();