C# 守护进程的介绍及实现详解

using System.Diagnostics;

var p = Process.GetProcessesByName("notepad")[0];
p.EnableRaisingEvents = true;
p.Exited += P_Exited;

Console.ReadLine();

void P_Exited(object? sender, EventArgs e)
{
    p = Process.Start("notepad");

    p.EnableRaisingEvents = true;
    p.Exited += P_Exited;
}

using System.Management;

// 查询进程创建 1秒钟通知
var qCreate = new WqlEventQuery($"__InstanceCreationEvent", TimeSpan.FromSeconds(1), $"TargetInstance isa \"Win32_Process\" and TargetInstance.Name = 'Notepad.exe'");

// 查询进程关闭 1秒钟通知
var qDelete = new WqlEventQuery($"__InstanceDeletionEvent", TimeSpan.FromSeconds(1), $"TargetInstance isa \"Win32_Process\" and TargetInstance.Name = 'Notepad.exe'");

// 创建事件查询的监听器
ManagementEventWatcher wCreate = new ManagementEventWatcher(qCreate);
ManagementEventWatcher wDelete = new ManagementEventWatcher(qDelete);

// 注册事件
wCreate.EventArrived += (sender, e) =>
{
    Console.WriteLine($"进程启动：{GetInfo(e.NewEvent)}");
};

wDelete.EventArrived += (sender, e) =>
{
    Console.WriteLine($"进程关闭：{GetInfo(e.NewEvent)}");
};

// 开始监听
wCreate.Start();
wDelete.Start();
Console.ReadLine();

static string GetInfo(ManagementBaseObject obj)
{
    var instance = obj["TargetInstance"] as ManagementBaseObject;
    return $"{instance["Name"]}-{instance["ProcessId"]}";
}