泛型编程去掉字段重复数据的方法

public partial class v_myjoinedcloudrespository

{

        public list<v_myjoinedcloud> getdistinctjoinedcloud(string cloudname,long expertid)
        {
            var lamd = from p in db.v_myjoinedcloud
                       where p.status == 1 && p.companyname.contains(cloudname) && p.expertid==expertid
                       select p;

            list<v_myjoinedcloud> list = new list<v_myjoinedcloud>();
            if (lamd!=null&&lamd.count()>0)
            {
                list = lamd.tolist();
                list = list.distinct(new companynamecomparer()).tolist();
            }
            return list;
        }

}

public class companynamecomparer : iequalitycomparer<v_myjoinedcloud>
    {
        public bool equals(v_myjoinedcloud x, v_myjoinedcloud y)
        {
            if (x == null)
                return y == null;
            return x.companyid == y.companyid;
        }

        public int gethashcode(v_myjoinedcloud obj)
        {
            if (obj == null)
                return 0;
            return obj.companyid.gethashcode();
        }
    }