C# Timer用法有哪些呢？我们在使用C# Timer时都会有自己的一些总结，那么这里向你介绍3种方法，希望对你了解和学习C# Timer使用的方法有所帮助。

关于C# Timer类  在C#里关于定时器类就有3个

C# Timer使用的方法1.定义在System.Windows.Forms里

C# Timer使用的方法2.定义在System.Threading.Timer类里  "

C# Timer使用的方法3.定义在System.Timers.Timer类里

下面我们来具体看看这3种C# Timer用法的解释：

◆System.Windows.Forms.Timer

应用于WinForm中的，它是通过Windows消息机制实现的，类似于VB或Delphi中的Timer控件，内部使用API  SetTimer实现的。它的主要缺点是计时不精确，而且必须有消息循环，Console  Application(控制台应用程序)无法使用。

◆System.Timers.Timer

和System.Threading.Timer非常类似，它们是通过.NET  Thread  Pool实现的，轻量，计时精确，对应用程序、消息没有特别的要求。

◆System.Timers.Timer还可以应用于WinForm，完全取代上面的Timer控件。它们的缺点是不支持直接的拖放，需要手工编码。

            //实例化Timer类，设置间隔时间为10000毫秒； System.Timers.Timer t = new System.Timers.Timer(1000);//到达时间的时候执行注册事件t.Elapsed += (obj,e) => {Console.WriteLine("ok");};//设置是执行一次（false）还是一直执行(true)； t.AutoReset = true;//是否执行System.Timers.Timer.Elapsed注册事件；   t.Enabled = true;Console.ReadKey();

javascript 对应的

setInterval(funciont(){xxxxx},1000)一直执行

setTimeout(function(){xxxxx},1000)只执行一次

需求：规定时间启动定时器(比如早上下午6点启动,上午就管理员运行程序 )

code：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data;
using System.Threading;namespace CsDemo
{class Program{static System.Timers.Timer t = null;static Thread td = null;static bool isOpenTimers = false;static bool isThreadFalg = true;static void Main(string[] args){Timers(statrDay() * msecTime);//statrDay() * msecTime读取配置文件或者指定时间
Threads();}private static void Threads(){td = new Thread(ThreadMethod);td.IsBackground = true;td.Start(td);}/// <summary>定时器/// </summary>public static void Timers(double Time){t = new System.Timers.Timer(Time);t.Elapsed += (obj, e) =>{//Do something
            };t.AutoReset = true;t.Enabled = true;}/// <summary>线程 指定时间启动定时器/// </summary>private static void ThreadMethod(object td){var temp = td as Thread;while (isThreadFalg){int hour = DateTime.Now.Hour;if (hour >= hourTime)//hourTime 读取配置文件 下午6点
                {if (!isOpenTimers){t.Start();Thread.Sleep(1000);temp.Abort();}}Thread.Sleep(300000);}}}
}

2：问题 定时器里面方法没有执行完 下一次又启动了 但是我希望排队的方式运行 (上次任务结束才开始)

code：

        /// <summary>定时器/// </summary>public static void Timers(double Time){t = new System.Timers.Timer(Time);t.Elapsed += (obj, e) =>{t.Stop();//Do something
                t.Start();};t.AutoReset = true;t.Enabled = true;t.Start();}

3：需求3 假设定时器7天运行一次 1号开启 突然bug或者意外3号天挂了  第4天开启 这个时候  7号继续执行 不能等到4+7 11号执行

原理：

每次运行定时器动态计算时间：异常时候写入奔溃时间

1：

   Timers(statrDay() * msecTime);//mescTime 为 86400000 一天 这样项目原因不考虑public double statrDay(){DateTime lastDay = DateTime.Parse(nextDayStar);TimeSpan ts = lastDay - DateTime.Now;var dayTemp = ts.Days;if (dayTemp >= pushTime || dayTemp <= 0) dayTemp = pushTime;return dayTemp; }

2：Timer Elapsed方法每次运行写入下次启动时间

Logging.GetInstance().InsertNextDayStart(DateTime.Now.AddDays(pushTime).ToString());pushTime=7

3：程序奔溃写入下次启动时间

  public static void InsertLog(){ThreadPool.QueueUserWorkItem(o =>{while (true){try{if (tempLog.Count > 0){string errorMsg = tempLog.Dequeue();Logging.GetInstance().WriteLog(errorMsg, path);Logging.GetInstance().InsertNextDayStart(DateTime.Now.AddDays(frm.pushTime).ToString());Thread.Sleep(30);}else{Thread.Sleep(30000);}}catch (Exception ex){tempLog.Enqueue("系统错误" + GetExceptionMsg(ex as Exception, ex.ToString()));}}});}

为队列 public static Queue<string> tempLog = new Queue<string>();

详细代码：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using DAL;
using Redslide.HttpLib;
using System.Web;
using System.Threading;
using System.Collections.Concurrent;
using System.Reflection;
using System.Threading.Tasks;
using Tool.Entity;
using System.Diagnostics;
using System.Configuration;
using System.IO;
using System.Web.Script.Serialization;namespace IllegalMsgPush
{public partial class frWz : Form{#region 全局变量System.Timers.Timer t = null;Thread td = null;bool isOpenTimers = false;bool isThreadFalg = true;string urlCopy = null; ConcurrentDictionary<string, userList> dicUser=null;static Task tk = null;/// <summary>/// 违章消息推送时间启动(单位小时)/// </summary>public int hourTime = 0;/// <summary>/// 违章消息推送定时推送(单位天)/// </summary>public int pushTime = 0;/// <summary>/// 下次启动时间(day)/// </summary>public string nextDayStar =null;Action<string> acCarMsgShow = null;public int holdID;public int msecTime;/// <summary>同步锁用于删除队列信息与添加消息/// </summary>private static object _objfrWzMsgLock = new object();#endregionpublic frWz(){InitializeComponent();this.SizeChanged += (o, e) =>{if (this.WindowState == FormWindowState.Minimized){this.Hide();this.notifyIcon1.Visible = true;}};InitializationParameter();Timers(statrDay() * msecTime);Threads();}#region      -sql command/// <summary>用户以及子用户下面的车/// </summary>private DataTable LoadCarChildList(){var sql = string.Format(@"with cte as(select userName ,userID from std_UserInfo where isDeleted=0) select a.ObjectID,a.vehicleNum,d.EngineCode,d.ShelfCode ,c.userNamefrom dbo.Table_F_GetObjectInfoByObjUserHoldID(0,1,1) a left join std_ObjAppend d with (nolock) on  a.ObjectID=d.ObjectID left join std_UserObj   b with (nolock)  on  d.ObjectID=b.ObjectID left hash join cte c on  b.userID=c.userID where c.userName is not null", holdID);return SqlHelper.ExecuteDataset(sql).Tables[0];}public void InsertPushInfo(string objectID, string vehclieNum, string userName){Task.WaitAll(tk);StringBuilder sql = new StringBuilder();var temp = objectID + "_" + userName;if (ContainsKey(temp)){sql.Append(@"INSERT INTO personal_PushInfo(Contype,context,UserName,OBDTerminalNo ,voiceName             ,isDeleted ,RcvTime ,TypeID ,ID ,VehicleNum,ItemID,voiceDetail,GPSTime ,CerFileName,CerPassword,PushServerType)");sql.AppendFormat(@"VALUES('违章','您有一条新的违章消息','{0}','{1}','109.wav',0,getdate(),2,'{2}','{3}',109,'您有一条新的违章消息',getdate(),'{4}','{5}',1)", dicUser[temp].UserName              //UserName, dicUser[temp].OBDTerminalNo         //OBDTerminalNo, int.Parse(objectID)                 //ID  -车辆ID ObjectID, vehclieNum                          //VehicleNum, dicUser[temp].CerFileName           //CerFileName 安卓null , dicUser[temp].CerPassword           //CerPassword
                                          );SqlHelper.ExecuteNonQuery(sql.ToString());}else{string str = "key不存在异常出现在ID: " + objectID + "车牌:" + vehclieNum + "userName:" + userName;Logging.GetInstance().WriteLog(str, Program.carListLog);}}public void LoadUserList(){dicUser = new ConcurrentDictionary<string, userList>();tk = Task.Factory.StartNew(() =>{var sql = "SELECT UserName,OBDTerminalNo,ObjectID,CerFileName,CerPassword  FROM std_UserObj  a left hash join std_UserInfo b on a.UserID=b.UserID WHERE b.isDeleted=0";var temp = SqlHelper.ExecuteDataset(sql).Tables[0];if (temp != null || temp.Rows.Count > 0){var dataType = typeof(userList);var infos = dataType.GetProperties(BindingFlags.Instance | BindingFlags.Public);foreach (DataRow row in temp.Rows.AsParallel()){var obj = (userList)Activator.CreateInstance(dataType);foreach (DataColumn col in temp.Columns.AsParallel()){try{foreach (PropertyInfo info in infos){if (info.Name.ToLower() == col.ColumnName.ToLower()){if (row[col].GetType().FullName != "System.DBNull"){info.FastSetValue(obj, row[col]);}}}}catch{}}Add(obj.ObjectID.ToString() + "_" + obj.UserName, obj);}}});}public void csDemo(){if (this.txtContent.InvokeRequired){this.txtContent.Invoke(acCarMsgShow, "执行一次");}string str = @"INSERT INTO personal_PushInfo(Contype,context,UserName,OBDTerminalNo ,voiceName,isDeleted ,RcvTime ,TypeID ,ID ,VehicleNum,ItemID ,voiceDetail,GPSTime ,CerFileName,CerPassword,PushServerType)VALUES('报警','车辆设防','chen','d3e0d773cd1dde1a939bde8b4ea5605ffb0a9aa3dd07be1dbb8213f6f7b64862','79.wav',0,getdate(),1,73252,'粤Blyq', 79,'您有一条新的违章消息',getdate(),'carGeniusP_erp_dev.pem','123456',0)";SqlHelper.ExecuteNonQuery(str);}#endregionprivate void HttpGet(){var dt = LoadCarChildList();if (dt == null || dt.Rows.Count == 0) return;JavaScriptSerializer js = new JavaScriptSerializer();foreach (DataRow item in dt.Rows){lock (_objfrWzMsgLock){var carCode = item["EngineCode"].ToString();if (string.IsNullOrEmpty(carCode)) continue;var carNumber = item["ShelfCode"].ToString();if (string.IsNullOrEmpty(carNumber)) continue;var objectID = item["ObjectID"].ToString();var vehclieNum = item["vehicleNum"].ToString();var userName = item["userName"].ToString();string url = string.Format(urlCopy, HttpUtility.UrlEncode(vehclieNum, System.Text.Encoding.UTF8), GetLastStr(carCode, 6), GetLastStr(carNumber, 6));Request.Get(url, null, result =>{var json = (Dictionary<string, object>)js.DeserializeObject(result);if (json == null) return;if (bool.Parse(json["Success"].ToString()) && bool.Parse(json["HasData"].ToString())){var tempMsg = "车牌ID：" + objectID  + "--车牌号：" + vehclieNum + "--用户名:" + userName;if (this.txtContent.InvokeRequired) this.txtContent.Invoke(acCarMsgShow, tempMsg);InsertPushInfo(objectID, vehclieNum, userName);Logging.GetInstance().WriteLog(tempMsg, Program.carListLog);}else {Logging.GetInstance().WriteLog(result.ToString(), Program.carListLog);}}, e =>{string str = "http请求错误" + Program.GetExceptionMsg(e, string.Empty);Logging.GetInstance().WriteLog(str, Program.carListLog);});}}}#region    eventprivate void button1_Click(object sender, EventArgs e){if (MessageBox.Show("要重新启动嘛？", "提示", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.Yes){t = null;td = null;notifyIcon1 = null;Application.Restart();}}private void frWz__Shown(object sender, EventArgs e){this.Visible = true;notifyIcon1.Visible = true;notifyIcon1.Icon = this.Icon;}private void frWz_FormClosing(object sender, FormClosingEventArgs e){if (notifyIcon1 != null){e.Cancel = true;this.Visible = false;}}private void ToolStripMenuItem_Show_Click(object sender, EventArgs e){this.Show();this.WindowState = FormWindowState.Normal;}private void ToolStripMenuItem_Exit_Click(object sender, EventArgs e){if (MessageBox.Show("你确定退出吗？", "提示", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.Yes){t = null;td = null;dicUser = null;notifyIcon1 = null;this.Close();}}private void notifyIcon1_MouseClick(object sender, MouseEventArgs e){if (e.Button == MouseButtons.Left){notifyIcon1.Visible = true;this.Show();this.WindowState = FormWindowState.Normal;}else{Point pt = new Point();pt = Control.MousePosition;contextMenuStrip1.Show(pt);}}#endregionprivate void Threads(){td = new Thread(ThreadMethod);td.IsBackground = true;td.Start(td);}/// <summary>定时器/// </summary>public void Timers(double Time){t = new System.Timers.Timer(Time);t.Elapsed += (obj, e) =>{t.Stop();Logging.GetInstance().InsertNextDayStart(DateTime.Now.AddDays(pushTime).ToString());isOpenTimers = true;LoadUserList();HttpGet();t.Interval = pushTime * msecTime;t.Start();};t.AutoReset = true;t.Enabled = true;}/// <summary>初始化参数和变量/// </summary>private void InitializationParameter(){Logging.GetInstance().CreateFile(Program.path, Program.carListLog);urlCopy = ConfigRead.GetInstance().pushUrlValue();hourTime = ConfigRead.GetInstance().hourTimeValue();pushTime = ConfigRead.GetInstance().pushDayValue();nextDayStar = Logging.GetInstance().ReadNextDayStart();holdID = ConfigRead.GetInstance().holdIDValue();msecTime = ConfigRead.GetInstance().msecTimeValue();acCarMsgShow = (strMsg) =>{txtContent.AppendText("请求成功消息：" + strMsg + "\r\n");};}/// <summary>线程 指定时间启动定时器/// </summary>private void ThreadMethod(object td){var temp = td as Thread;while (isThreadFalg){int hour = DateTime.Now.Hour;if (hour >= hourTime){if (!isOpenTimers){t.Start();Thread.Sleep(1000);temp.Abort();}}Thread.Sleep(300000);}}#region IDictionary<string,ResultType> 成员public void Add(string key, userList value){dicUser.TryAdd(key, value);}public bool ContainsKey(string key){return dicUser.ContainsKey(key);}public ICollection<string> Keys{get { return dicUser.Keys; }}public bool Remove(string key){userList val;return dicUser.TryRemove(key, out val);}public bool TryGetValue(string key, out userList value){return dicUser.TryGetValue(key, out value);}public ICollection<userList> Values{get { return dicUser.Values; }}public userList this[string key]{get{return dicUser[key];}set{dicUser[key] = value;}}#endregionpublic void updateConfig(string key, string value){var config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);if (config.AppSettings.Settings[key] != null){config.AppSettings.Settings[key].Value = value;}else{config.AppSettings.Settings.Add(key, value);}config.Save(ConfigurationSaveMode.Modified);ConfigurationManager.RefreshSection("appSettings");}public double statrDay(){DateTime lastDay = DateTime.Parse(nextDayStar);TimeSpan ts = lastDay - DateTime.Now;var dayTemp = ts.Days;if (dayTemp >= pushTime || dayTemp <= 0) dayTemp = pushTime;return dayTemp; }public string GetLastStr(string str, int num){if (str.Length > num){str = str.Substring(str.Length - num, num);}return str;}}public class userList{public string UserName { get; set; }public string OBDTerminalNo { get; set; }public int ObjectID { get; set; }public string CerPassword { get; set; }public string CerFileName { get; set; }}
}

View Code

Program

using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Forms;
using System.Text;
using Tool.Entity;
using System.Diagnostics;
using System.Threading;
using System.IO;
using System.Collections;namespace IllegalMsgPush
{static class Program{public static frWz frm = null;public static string path = "";public static string carListLog = "";public static Queue<string> tempLog = new Queue<string>();/// <summary>/// 应用程序的主入口点。/// </summary>
        [STAThread]static void Main(){#region 应用程序的主入口点try{bool flag;Mutex mutex = new Mutex(true, Application.ProductName, out flag);if (flag){path = string.Format("{0}{1}", AppDomain.CurrentDomain.BaseDirectory, @"/log/");carListLog = string.Format("{0}{1}", AppDomain.CurrentDomain.BaseDirectory, @"/carListLog/");InsertLog();//设置应用程序处理异常方式：ThreadException处理
                    Application.SetUnhandledExceptionMode(UnhandledExceptionMode.CatchException);//处理UI线程异常Application.ThreadException += new System.Threading.ThreadExceptionEventHandler(Application_ThreadException);//处理非UI线程异常AppDomain.CurrentDomain.UnhandledException += new UnhandledExceptionEventHandler(CurrentDomain_UnhandledException);Application.EnableVisualStyles();Application.SetCompatibleTextRenderingDefault(false);frm = new frWz();Application.Run(frm);//释放 System.Threading.Mutex 一次
                    mutex.ReleaseMutex();}else{MessageBox.Show(null, "相同的程序已经在运行了,请不要同时运行多个程序!\n\n这个程序即将退出!", Application.ProductName, MessageBoxButtons.OK, MessageBoxIcon.Warning);Application.Exit();}}catch (Exception ex){string str = "系统错误" + GetExceptionMsg(ex, string.Empty);tempLog.Enqueue(str);}#endregion}static void Application_ThreadException(object sender, System.Threading.ThreadExceptionEventArgs e){string str = "系统错误" + GetExceptionMsg(e.Exception, e.ToString());tempLog.Enqueue(str);}static void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e){string str = "系统错误" + GetExceptionMsg(e.ExceptionObject as Exception, e.ToString());tempLog.Enqueue(str);}public static string GetExceptionMsg(Exception ex, string backStr){StringBuilder sb = new StringBuilder();sb.AppendLine("****************************异常文本****************************");sb.AppendLine("【出现时间】：" + DateTime.Now.ToString());if (ex != null){sb.AppendLine("【异常类型】：" + ex.GetType().Name);sb.AppendLine("【异常信息】：" + ex.Message);sb.AppendLine("【堆栈调用】：" + ex.StackTrace);}else{sb.AppendLine("【未处理异常】：" + backStr);}sb.AppendLine("***************************************************************");return sb.ToString();}public static void InsertLog(){ThreadPool.QueueUserWorkItem(o =>{while (true){try{if (tempLog.Count > 0){string errorMsg = tempLog.Dequeue();Logging.GetInstance().WriteLog(errorMsg, path);Logging.GetInstance().InsertNextDayStart(DateTime.Now.AddDays(frm.pushTime).ToString());Thread.Sleep(30);}else{Thread.Sleep(30000);}}catch (Exception ex){tempLog.Enqueue("系统错误" + GetExceptionMsg(ex as Exception, ex.ToString()));}}});}}
}

View Code

配置文件：

<?xml version="1.0"?>
<configuration>
<startup><supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/></startup><appSettings><!--路精灵所属单位ID配置 start--><add key="holdID" value="1"/><!--路精灵所属单位ID配置end--><!--违章消息推送时间天数start (正整数)--><add key="pushDay" value="14"/><!--违章消息推送时间天数end (正整数)--><!--违章消息推送几点启动start (正整数0-24)--><add key="hourTime" value="6"/><!--违章消息推送几点启动结束end (正整数)--><!--违章消息URL start--><add key="pushUrl" value="xxxx"/><!--违章消息URL end--><!--违章消息推送毫秒 (默认86400000 测试可调整修改)--><add key="msecTime" value="86400000"/><!--违章消息推送毫秒end (正整数)--></appSettings><connectionStrings><!--数据库连接串开始--><add name="ConnStr" connectionString="xxxxx"/><!--数据库连接串结束-->        </connectionStrings>
</configuration>

View Code

转载于:https://www.cnblogs.com/y112102/archive/2013/06/06/3121615.html

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