c#
//新建类  Student.cs
class Student {
  private int age;
  private string name;
  private long id;

  public Student(int age, string name, long id) {
    this.age = age;
    this.name = name;
    this.id = id;
  }
  //  带函数方法开始  == !=
  public static bool operator == (Student s1, Student s2) {
    if (s1.age == s2.age && s1.name == s2.name && s1.id == s2.id) {
      return true;
    }
    return false;
  }
  public static bool operator != (Student s1, Student s2) {
    bool result = s1 == s2;
    return !result;
  }
  //  带函数方法结束
}

c#
//使用  Program.cs
Student s1 = new Student(20, "张三", 12903);
Student s2 = new Student(20, "张三", 12903);

Student s3 = s1;
Console.WriteLine(s1 == s2);
Console.WriteLine(s1 == s3);
// 上面方法带函数方法  比较的是参数值   值都为True
// 上面方法不带函数方法  比较的是引用   值为 Flase   True