List<T>Distinct 过滤

public class TestDuplicateDefine : IEqualityComparer<student>
    {
        public bool Equals(student x, student y)
        {
            return x.name == y.name;
        }

        public int GetHashCode(student obj)
        {
            return obj.ToString().GetHashCode();
        }
    }

    public class student
    {
        public string name { get; set; }
        public int id { get; set; }
    }

private void button1_Click(object sender, EventArgs e)
        {
            List<student> list = new List<student>();
            list.Add(new student { name = "111", id = 1 });
            list.Add(new student { name = "222", id = 2 });
            list.Add(new student { name = "111", id = 3 });
            list.Add(new student { name = "333", id = 4 });

            List<student> aa = list.Distinct(new TestDuplicateDefine()).ToList();
        }