一道书上的题 我想问问！！！1

using System;namespace DelegateRegisterFinish
{

class Student
{
                  ();//定义委托 public delegate void DelegateRegisterFinish
                   //通过委托定义事件
public event DelegateRegisterFinish RegisterFinish; private string _name; public Student(string name)
{

this._name = name;

} public void Register()
{

Console.WriteLine("学生{0}进行注册",_name);
 
                        if(RegisterFinish !=null)

                         {//引发事件

                          RegisterFinish();

}


}
}
class RegisterStudent
{
static void Main()
{

Console.WriteLine("输入注册学生的姓名：");
String stuname = Console.ReadLine();
Student s = new Student(stuname);
                   
                   //订阅Student类的DelegateRegisterFinish事件

                       s.RegisterFinish +=new   
 
                DelegateRegisterFinish.Student.DelegateRegisterFinish(
           
                 ！！！！！这句什么意思啊  -------- s_RegisterFinish);

}
private static void s_RegisterFinish()<-----—
{                                                      |
                                                                |
Console.WriteLine("register OK congrutulations");      |
                                                                |
                                                                |
}                                                      | 
                                                       |
}                                                      |
                                                                |
}                                                               |
                                                                |
                                                                |
                                                                |
DelegateRegisterFinish.Student.DelegateRegisterFinish(           ——                                                                     |
                                                                     |
                 s_RegisterFinish);----括号里面的 是什么意思啊   是不是 上面的方法实现了它啊！！！！