拉姆达表达式对集合去重
IList<StudentList> distinct = result.PageList.Where((x, i) => result.PageList.ToList().FindIndex(z => z.Name== x.Name) == i).ToList();
IList<StudentList> distinct = result.PageList.Where((x, i) => result.PageList.ToList().FindIndex(z => z.Name== x.Name) == i).ToList();