List之Union(),Intersect(),Except() 即并集，交集，差集運算。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Sample2
{
    class Program
    {
        static void Main(string[] args)
        {
            //List之Union(),Intersect(),Except() 即并集，交集，差集運算
            IList<Student> Students1 = new List<Student>();
            Students1.Add(new Student(1, false, "張三", "深圳"));
            Students1.Add(new Student(2, false, "李四", "廣州"));
            Students1.Add(new Student(3, false, "王五", "珠海"));
            Students1.Add(new Student(4, false, "趙六", "東莞"));

            IList<Student> Students2 = new List<Student>();
            Students2.Add(new Student(1, false, "張三", "深圳"));
            Students2.Add(new Student(5, false, "李七", "廣州"));
            Students2.Add(new Student(6, false, "孫八", "深圳"));
            Students2.Add(new Student(7, true, "趙燕", "深圳"));

            //自定義比較規則
            var bingji = Students1.Union(Students2, new StudentListEquality()).ToList();//并集（AB集合所有項）
            var jiaoji = Students1.Intersect(Students2, new StudentListEquality()).ToList();//交集 (AB集合共同項)
            var chaji = Students1.Except(Students2, new StudentListEquality()).ToList();//差集（A集合有,B沒有）

            Console.WriteLine("以下是并集的結果");
            bingji.ForEach(x =>
            {
                Console.WriteLine(x.Id.ToString() + "    " + x.Sex.ToString() + "   " + x.Name.ToString() + " " + x.Address.ToString());

            });

            Console.WriteLine("以下是交集的結果");
            jiaoji.ForEach(x =>
            {
                Console.WriteLine(x.Id.ToString() + "    " + x.Sex.ToString() + "   " + x.Name.ToString() + " " + x.Address.ToString());

            });

            Console.WriteLine("以下是差集的結果");
            chaji.ForEach(x =>
            {
                Console.WriteLine(x.Id.ToString() + "    " + x.Sex.ToString() + "   " + x.Name.ToString() + " " + x.Address.ToString());

            });
            Console.ReadKey();
        }
    }

    public class Student
    {
        public Student(int id, bool sex, String name, String address)
        {
            this.Id = id;
            this.Sex = sex;
            this.Name = name;
            this.Address = address;
        }
        public int Id { get; set; }
        public bool Sex { get; set; }
        public String Name { get; set; }
        public String Address { get; set; }

    }

    public class StudentListEquality : IEqualityComparer<Student>
    {
        public bool Equals(Student x, Student y)
        {
            return x.Id == y.Id && x.Name == y.Name && x.Address == y.Address && x.Sex == y.Sex;
        }
        public int GetHashCode(Student obj)
        {
            return (obj == null) ? 0 : obj.ToString().GetHashCode();
        }
    }
}