1-) C# RMOS - class object distinct model or list string distinc

 List<RezAktarModel> rezAktarModels = new List<RezAktarModel>();

 ...

 ...

 rezAktarModels = rezAktarModels.GroupBy(car => new { car.otel, car.front }).Select(g => g.First()).ToList();

*** DİĞER ***

List<string> uniques = str.Split(',').Distinct().ToList();

*** DİĞER1 ***

List<string> linkListOnceki= new List<string>();

..

..

List<string> linkList = new List<string>();

linkList.AddRange(linkListOnceki.Distinct());

*** ÇİFTLEYEN KAYITLARI BULMA***

public void ciftleyenDuzelt(List<MasaPostaModel> masaPostaModels)

        {

var duplicateItems = masaPostaModels.GroupBy(x => x.Masa_No).Where(x => x.Count() > 1).Select(x => x.Key).ToList();

}

VEYA

  var duplicateItems = masaPostaModels.GroupBy(c => new

                {

                    c.Masa_No,

                    c.Masa_Fisno

                }).Where(x => x.Count() > 1).Select(c => new

                {

                    c.FirstOrDefault().Masa_No,

                    c.FirstOrDefault().Masa_Fisno

                }).ToList();