list集合中指定字段去重

//集合指定字段去重（宗地代码）
List<FDCQClient> resultFDCQ = new List<FDCQClient>();
var resultdis=resultFDCQ.Distinct(new ModelComparer()).ToList();
public class ModelComparer : IEqualityComparer<FDCQClient>
        {
            public bool Equals(FDCQClient x, FDCQClient y)
            {
                return x.ZDDM == y.ZDDM;
            }
            public int GetHashCode(FDCQClient obj)
            {
                return obj.ZDDM.GetHashCode();
            }
        }