新建一个form程序，在调试窗口输出执行过程；

为了使用Debug.WriteLine，添加 using System.Diagnostics;

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Diagnostics;namespace myevhd
{public class Headmaster{public event EventHandler<string> ActHandler;public void Come(){Debug.WriteLine("校长来了");ActHandler(null, "王校长");}}public class Students{public void Action_Master(object sender, string name){Debug.WriteLine("全班起立，喊" + name + "好；");}}public partial class Form1 : Form{public Form1(){Students student = new Students();Headmaster master = new Headmaster();master.ActHandler += student.Action_Master;master.Come();InitializeComponent();}}
}