定时器_在.net core3.0 webapi中添加自定义定时器功能

　　前言：想在.net framework环境使用自定义定时器的话，参考我的另一篇文章：https://www.cnblogs.com/lxhbky/p/10242839.html

　　想在.net core中使用定时器功能，需要借助一个服务接口：IHostedService,   继承并实现对应方法，最后再setup.cs类中添加注册服务：services.AddHostedService<实现服务类>();   既然要写计时器的服务器，那么该实现类就要包含定时器，本篇博客也是借助System.Timers.Timer类封装的。

　　下面展示具体代码：

　　1-公用基类：

　　

public class ModelBase
    {
        protected IServiceProvider Services { get; set; }
        protected IWebHostEnvironment WebHostEnvironment { get; set; }
        /// <summary>
        /// 配置帮助类
        /// </summary>
        protected ConfigHelper ConfigHelper { get; set; }
        /// <summary>
        /// 等同于ASP.NET里面的WebCache(HttpRuntime.Cache)
        /// </summary>
        protected IMemoryCache MemoryCache { get; set; }

        /// <summary>
        /// 日志
        /// </summary>
        protected ILogger Logger { get; set; }

        /// <summary>
        /// 授权帮助
        /// </summary>
        protected OAuthHelper OAuthHelper { get; set; }

        /// <summary>
        /// HttpClient帮助工厂
        /// </summary>
        protected IHttpClientFactory HttpClientFactory { get; set; }


        public ModelBase(params object[] @params)
        {
            foreach (var item in @params)
            {
                if (item is IServiceProvider)
                {
                    this.Services = (IServiceProvider)item;
                }
                else if (item is IWebHostEnvironment)
                {
                    this.WebHostEnvironment = (IWebHostEnvironment)item;
                }
                else if (item is ConfigHelper)
                {
                    this.ConfigHelper = (ConfigHelper)item;
                }
                else if (item is IMemoryCache)
                {
                    this.MemoryCache = (IMemoryCache)item;
                }
                else if (item is ILogger)
                {
                    this.Logger = (ILogger)item;
                }
                else if (item is OAuthHelper)
                {
                    this.OAuthHelper = (OAuthHelper)item;
                }
                else if (item is IHttpClientFactory)
                {
                    this.HttpClientFactory = (IHttpClientFactory)item;
                }
                
            }

        }
    }

　　

　　2-计时器封装类：

　　相对于.net framework文章计时器部分的类做了对应优化，更加简化了：

using Microsoft.Extensions.Logging;
using PaymentAccountAPI.Common;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.Timers;

namespace PaymentAccountAPI.Helper
{
    /// <summary>
    /// 定时周期帮助类
    /// </summary>
    public class TimeCycleHelp : ModelBase
    {
        public TimeCycleHelp(ILogger<TimeCycleHelp> logger) : base(logger)
        {
            this.Timer = new System.Timers.Timer();
        }

        /// <summary>
        /// 服务专属计时器
        /// </summary>
        private System.Timers.Timer Timer;

        /// <summary>
        /// 默认计时器时间间隔1秒（提高计时器开始时间准确度）
        /// </summary>
        private double DefaultTimerInterval = 1 * 1000;

        /// <summary>
        /// 设置多个循环周期
        /// </summary>
        private List<TimeCycle> TimeCycleList { get; set; }


        /// <summary>
        /// 更新一个计时器的计时周期
        /// </summary>
        /// <param name="newTimerInterval">新的计时周期</param>
        /// <param name="isFirstStart">是否是首次更新计时器周期</param>
        private void UpdateTimeInterval(double newTimerInterval, bool isFirstStart = false)
        {
            if (this.Timer != null && newTimerInterval > 0)
            {
                this.Timer.Stop();
                if (this.Timer.Interval != newTimerInterval)
                {
                    this.Timer.Interval = newTimerInterval;
                }
                if (isFirstStart)
                {
                    this.Timer.Elapsed += new System.Timers.ElapsedEventHandler(this.ServiceAction);
                }
                this.Timer.AutoReset = true;
                this.Timer.Start();
            }
        }

        /// <summary>
        /// 内部辅助方法
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void ServiceAction(object sender, ElapsedEventArgs e)
        {
            List<TimeCycle> currentTimeCycleList = new List<TimeCycle>(0);

            DateTime now = DateTime.Now;
            DateTime cycleBeginTime;
            DateTime cycleEndTime;
            foreach (TimeCycle timeCycle in this.TimeCycleList)
            {
                cycleBeginTime = Convert.ToDateTime(timeCycle.BeginTime);
                cycleBeginTime = now.Date.AddHours(cycleBeginTime.Hour).AddMinutes(cycleBeginTime.Minute).AddSeconds(cycleBeginTime.Second);
                cycleEndTime = Convert.ToDateTime(timeCycle.EndTime);
                cycleEndTime = now.Date.AddHours(cycleEndTime.Hour).AddMinutes(cycleEndTime.Minute).AddSeconds(cycleEndTime.Second);
                if (cycleEndTime < cycleBeginTime)
                {
                    cycleEndTime = cycleEndTime.AddDays(1);
                }

                if (now >= cycleBeginTime && now <= cycleEndTime)
                {
                    //有最大执行次数限制或者没有限制
                    if (timeCycle.ActionExecutionTimes < timeCycle.MaxActionTimes || timeCycle.MaxActionTimes == 0)
                    {
                        TimeSpan timeSpan = now - cycleBeginTime;
                        bool isCanAction = (int)timeSpan.TotalSeconds % timeCycle.ActionSeconds == 0 ? true : false;
                        if (isCanAction)
                        {
                            timeCycle.ActionExecutionTimes++;
                            currentTimeCycleList.Add(timeCycle);
                        }
                    }
                }
                else
                {
                    //不在计时周期内，已执行次数清零
                    timeCycle.ActionExecutionTimes = 0;
                }
            }
            //找到当前循环周期后，执行周期内动作
            if (currentTimeCycleList.Count > 0)
            {
                currentTimeCycleList.ForEach(item =>
                {
                    //使用多线程执行任务，让代码快速执行
                    Task.Run(() => item.Action());
                });
            }
        }

        /// <summary>
        /// 开启计时器
        /// </summary>
        /// <param name="timeCycleArray"></param>
        public void Start(params TimeCycle[] timeCycleArray)
        {
            if (timeCycleArray != null && timeCycleArray.Length > 0)
            {
                if (this.TimeCycleList == null)
                {
                    this.TimeCycleList = new List<TimeCycle>(100);
                }
                this.TimeCycleList = timeCycleArray.ToList();

                //设置首次计时器周期（首次动作执行，是在计时器启动后在设置的时间间隔后做出的动作）
                this.UpdateTimeInterval(this.DefaultTimerInterval, true);
            }
        }

        /// <summary>
        /// 结束计时器
        /// </summary>
        public void Stop()
        {
            this.Timer.Stop();
        }

    }

    /// <summary>
    /// 计时周期类
    /// </summary>
    public class TimeCycle
    {
        /// <summary>
        /// 唯一标识
        /// </summary>
        public int ID { get; set; }
        /// <summary>
        /// 开始时间(误差1秒=取决于计时器默认时间间隔)
        /// </summary>
        public string BeginTime { get; set; }
        /// <summary>
        /// 结束时间
        /// </summary>
        public string EndTime { get; set; }
        /// <summary>
        /// 最大执行次数
        /// </summary>
        public int MaxActionTimes { get; set; }
        /// <summary>
        /// 计时周期内执行的动作(动作会在到达开始时间后的)
        /// </summary>
        public Action Action { get; set; }
        /// <summary>
        /// 动作执行时间间隔（秒）
        /// </summary>
        public int ActionSeconds { get; set; }
        /// <summary>
        /// 方法执行次数
        /// </summary>
        internal int ActionExecutionTimes { get; set; }

        public TimeCycle(int id, Action action, int actionSeconds) : this(id, "00:00:00", action, actionSeconds)
        {
        }

        public TimeCycle(int id, string beginTime, Action action, int actionSeconds) : this(id, beginTime, action, actionSeconds, 0)
        {
        }

        public TimeCycle(int id, string beginTime, Action action, int actionSeconds, int maxActionTimes) : this(id, beginTime, "23:59:59", action, actionSeconds, maxActionTimes)
        {
        }

        /// <summary>
        /// 基本构造器
        /// </summary>
        /// <param name="id">唯一标识</param>
        /// <param name="beginTime">开始时间</param>
        /// <param name="endTime">结束时间</param>
        /// <param name="action">要执行的任务</param>
        /// <param name="actionSeconds">任务执行时间间隔</param>
        /// <param name="maxActionTimes">最大执行次数</param>
        public TimeCycle(int id, string beginTime, string endTime, Action action, int actionSeconds, int maxActionTimes)
        {
            this.ID = id;
            this.BeginTime = beginTime;
            this.EndTime = endTime;
            this.Action = action;
            this.ActionSeconds = actionSeconds;
            this.MaxActionTimes = maxActionTimes;
        }
    }
}

　　3-webAPI服务封装类：

　　

using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;
using PaymentAccountAPI.Common;
using PaymentAccountAPI.Helper;
using PaymentAccountAPI.PaymentAccountHelper;
using System;
using System.Threading;
using System.Threading.Tasks;

namespace PaymentAccountAPI.Hangfire
{
    public class SyncToCMSService : ModelBase, IHostedService
    {private TimeCycleHelp _TimeCycleHelp { get; set; }

        public SyncToCMSService(ConfigHelper configHelper,
                                TimeCycleHelp timeCycleHelp, ILogger<SyncToCMSService> logger) : base(logger, configHelper)
        {this._TimeCycleHelp = timeCycleHelp;
        }

        public void SyncData()
        {
           //...需要执行的任务代码

            this.Logger.LogInformation($"定时任务：完成{currentDate.ToShortDateString()}的交易记录同步！");
        }



        public Task StartAsync(CancellationToken cancellationToken)
        {
            this.Logger.LogInformation($"定时任务：同步服务已启动...");

            //正式代码
            string syncBeginTime = this.ConfigHelper.GetAppSettingValue("SyncCMSBeginTime");
            string syncEndTime = this.ConfigHelper.GetAppSettingValue("SyncCMSEndTime");
            this._TimeCycleHelp.Start(new TimeCycle(999, syncBeginTime, syncEndTime, this.SyncData, 3600, 2));

            //测试代码
            //this._TimeCycleHelp.Start(new TimeCycle(999, "12:00:00", () =>
            //{
            //    this.Logger.LogInformation("test123");
            //}, 10, 3));

            return Task.CompletedTask;
        }

        public Task StopAsync(CancellationToken cancellationToken)
        {
            this.Logger.LogInformation($"同步服务已停止...");
            this._TimeCycleHelp.Stop();

            return Task.CompletedTask;
        }

    }
}

　　4-在startup.cs添加注册服务：

　　

            #region 添加定时任务

            services.AddSingleton<TimeCycleHelp>();

            services.AddHostedService<SyncToCMSService>();

            #endregion

　　5-部署到IIS站点项目时的注意事项（引用下面道友的一段话）：

       关于GenericHost的生存周期问题

　　如果你使用的是控制台启动，则此问题暂时可以忽略。

　　如果你使用的是站点项目，并且还是通过IIS启动，那么你可能要注意了，因为.net core 的站点自身是有HOST宿主处理，IIS是其上代理，其启动关闭，端口映射等由IIS内部完成。所以其依然受限于IIS的闲置回收影响，当IIS闲置回收时，其后的.Net Host也会被一同关闭，需要有新的请求进来时才会再次启动。不过鉴于当前任务处理已经如此简单，有个取巧的做法，实现一个站点自身的心跳检测任务，IIS默认20分钟回收，任务时间可以设为15分钟（你也可以设置IIS站点回收时间），当然如果你的任务如果没有那么严格的时间要求你也可以不用处理，因为回收后一旦接受到新的请求，任务会再次发起。

　　最后感谢一篇道友的文章：.Net Core 简单定时任务框架封装