C# NET framework

版本兼容

https://docs.microsoft.com/en-us/dotnet/framework/migration-guide/how-to-configure-an-app-to-support-net-framework-4-or-4-5

<startup useLegacyV2RuntimeActivationPolicy="true">
    <supportedRuntime version="v4.0"/>
    <supportedRuntime version="v2.0.50727"/>
</startup>

查询目前系统所用的.net framework版本

reg query "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\full" /v version

.NET Framework 4.x 程序到底运行在哪个 CLR 版本之上

vs2019 创建Windows Service

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.ServiceProcess;
using System.Text;
using System.Threading.Tasks;
namespace TestWindowsService
{
    public partial class Service1 : ServiceBase
    {
        public Service1()
        {
            InitializeComponent();
        }
        protected override void OnStart(string[] args)
        {
            try
            {
                this.WriteLog("Start Service!");
                this.ToDoSomeThings();
            }
            catch(Exception ex)
            {
            }
        }
        protected override void OnStop()
        {
        }
        private void ToDoSomeThings()
        {
            DateTime dateTime = DateTime.Now;
            if(dateTime.Hour == 14 && dateTime.Minute == 30)
            {
                int a = 0;
                for(int i=0;i<1000; i++)
                {
                    a += i;
                }
                this.WriteLog(a.ToString());
            }
        }
        private void WriteLog(string LogContent)
        {
            string FilePath = AppDomain.CurrentDomain.SetupInformation.ApplicationBase + "\\Log.txt";
            FileStream fileStream = null;
            if(File.Exists(FilePath))
            {
                fileStream = new FileStream(FilePath, FileMode.Append);
            }
            else
            {
                fileStream = new FileStream(FilePath, FileMode.OpenOrCreate);
            }
            StreamWriter streamWriter = new StreamWriter(fileStream);
            streamWriter.WriteLine(DateTime.Now + System.Environment.NewLine + LogContent);
            streamWriter.Close();
            fileStream.Close();
            GC.Collect();
        }
    }
}

安装/卸载 Windows Service

要以管理员的身份启动powershell或者cmd

安装服务

C:\windows\Microsoft.NET\Framework64\v4.0.30319\InstallUtil.exe  D:\workspace\workspace_net\Test
WindowsService\TestWindowsService\bin\Debug\TestWindowsService.exe

卸载服务

C:\windows\Microsoft.NET\Framework64\v4.0.30319\InstallUtil.exe /u D:\workspace\workspace_net\Test
WindowsService\TestWindowsService\bin\Debug\TestWindowsService.exe

启动服务

net start service_name

停止服务

net stop service_name