请参考https://blog.csdn.net/HybridTheory_/article/details/88382442
使用C#解析Cron表达式，得到执行时间class Cron
{
private int[] seconds = new int[60];
private int[] minutes = new int[60];
private int[] hours = new int[24];
private int[] days = new int[31];
private int[] month = new int[12];
private int[] weeks = new int[7];
//2019-2099年
private int[] year = new int[80];
public int[] Seconds { get => seconds; set => seconds = value; }
public int[] Minutes { get => minutes; set => minutes = value; }
public int[] Hours { get => hours; set => hours = value; }
public int[] Days { get => days; set => days = value; }
public int[] Month { get => month; set => month = value; }
public int[] Weeks { get => weeks; set => weeks = value; }
public int[] Year { get => year; set => year = value; }
public Cron()
{
for (int i = 0; i < 60; i++)
{
seconds[i] = 0;
minutes[i] = 0;
}
for (int i = 0; i < 24; i++)
{
hours[i] = 0;
}
for (int i = 0; i < 31; i++)
{
days[i] = 0;
}
for (int i = 0; i < 12; i++)
{
month[i] = 0;
}
for (int i = 0; i < 7; i++)
{
weeks[i] = 0;
}
for (int i = 0; i < 80; i++)
{
year[i] = 0;
}
}
public void Init()
{
for (int i = 0; i < 7; i++)
{
weeks[i] = 0;
}
for (int i = 0; i < 31; i++)
{
days[i] = 0;
}
}
}
///调用方法示例/// 在week上使用 5L表示本月最后一个星期五 /// 7L表示本月最后一个星期天 /// /// 在week上使用 7#3表示每月的第三个星期天 /// 2#4表示每月的第四个星期二 /// public class CronHelp { ////// Cron表达式转换(默认开始时间为当前) /// /// 表达式 ///最近5次要执行的时间 private static ListCronToDateTime(string cron) { try { List lits = new List (); Cron c = new Cron(); string[] arr = cron.Split(' '); Seconds(c, arr[0]); Minutes(c, arr[1]); Hours(c, arr[2]); Month(c, arr[4]); if (arr.Length < 7) { Year(c, null); } else { Year(c, arr[6]); } DateTime now = DateTime.Now; int addtime = 1; while (true) { if (c.Seconds[now.Second] == 1 && c.Minutes[now.Minute] == 1 && c.Hours[now.Hour] == 1 && c.Month[now.Month - 1] == 1 && c.Year[now.Year - 2019] == 1) { if (arr[3] != "?") { Days(c, arr[3], DateTime.DaysInMonth(now.Year, now.Month), now); int DayOfWeek = (((int)now.DayOfWeek) + 6) % 7; if (c.Days[now.Day - 1] == 1 && c.Weeks[DayOfWeek] == 1) { lits.Add(now); } } else { Weeks(c, arr[5], DateTime.DaysInMonth(now.Year, now.Month), now); int DayOfWeek = (((int)now.DayOfWeek) + 6) % 7; if (c.Days[now.Day - 1] == 1 && c.Weeks[DayOfWeek] == 1) { lits.Add(now); } } } if (lits.Count >= 5) { break; } c.Init(); if (!arr[1].Contains('-') && !arr[1].Contains(',') && !arr[1].Contains('*') && !arr[1].Contains('/')) { if (now.Minute == int.Parse(arr[1])) { addtime = 3600; } } else if (arr[0] == "0" && now.Second == 0) { addtime = 60; } now = now.AddSeconds(addtime); } return lits; } catch { return null; } } /// /// Cron表达式转换（自定义开始时间） /// /// 表达式 /// 开始时间 ///最近5次要执行的时间 private static ListCronToDateTime(string cron, DateTime now) { try { List lits = new List (); Cron c = new Cron(); string[] arr = cron.Split(' '); Seconds(c, arr[0]); Minutes(c, arr[1]); Hours(c, arr[2]); Month(c, arr[4]); if (arr.Length < 7) { Year(c, null); } else { Year(c, arr[6]); } int addtime = 1; while (true) { if (c.Seconds[now.Second] == 1 && c.Minutes[now.Minute] == 1 && c.Hours[now.Hour] == 1 && c.Month[now.Month - 1] == 1 && c.Year[now.Year - 2019] == 1) { if (arr[3] != "?") { Days(c, arr[3], DateTime.DaysInMonth(now.Year, now.Month), now); int DayOfWeek = (((int)now.DayOfWeek) + 6) % 7; if (c.Days[now.Day - 1] == 1 && c.Weeks[DayOfWeek] == 1) { lits.Add(now); } } else { Weeks(c, arr[5], DateTime.DaysInMonth(now.Year, now.Month), now); int DayOfWeek = (((int)now.DayOfWeek) + 6) % 7; if (c.Days[now.Day - 1] == 1 && c.Weeks[DayOfWeek] == 1) { lits.Add(now); } } } if (lits.Count >= 5) { break; } c.Init(); if (!arr[1].Contains('-') && !arr[1].Contains(',') && !arr[1].Contains('*') && !arr[1].Contains('/')) { if (now.Minute == int.Parse(arr[1])) { addtime = 3600; } } else if (arr[0] == "0" && now.Second == 0) { addtime = 60; } now = now.AddSeconds(addtime); } return lits; } catch { return null; } } /// /// Cron表达式转换(默认开始时间为当前) /// /// 表达式 ///最近要执行的时间字符串 public static string GetNextDateTime(string cron) { try { DateTime now = DateTime.Now; string[] arr = cron.Split(' '); if (IsOrNoOne(cron)) { string date = arr[6] + "/" + arr[4] + "/" + arr[3] + " " + arr[2] + ":" + arr[1] + ":" + arr[0]; if (DateTime.Compare(Convert.ToDateTime(date), now) >= 0) { return date; } else { return null; } } Cron c = new Cron(); Seconds(c, arr[0]); Minutes(c, arr[1]); Hours(c, arr[2]); Month(c, arr[4]); if (arr.Length < 7) { Year(c, null); } else { Year(c, arr[6]); } int addtime = 1; while (true) { if (c.Seconds[now.Second] == 1 && c.Minutes[now.Minute] == 1 && c.Hours[now.Hour] == 1 && c.Month[now.Month - 1] == 1 && c.Year[now.Year - 2019] == 1) { if (arr[3] != "?") { Days(c, arr[3], DateTime.DaysInMonth(now.Year, now.Month), now); int DayOfWeek = (((int)now.DayOfWeek) + 6) % 7; if (c.Days[now.Day - 1] == 1 && c.Weeks[DayOfWeek] == 1) { return now.ToString("yyyy/MM/dd HH:mm:ss"); } } else { Weeks(c, arr[5], DateTime.DaysInMonth(now.Year, now.Month), now); int DayOfWeek = (((int)now.DayOfWeek) + 6) % 7; if (c.Days[now.Day - 1] == 1 && c.Weeks[DayOfWeek] == 1) { return now.ToString("yyyy/MM/dd HH:mm:ss"); } } } c.Init(); if (!arr[1].Contains('-') && !arr[1].Contains(',') && !arr[1].Contains('*') && !arr[1].Contains('/')) { if (now.Minute == int.Parse(arr[1])) { addtime = 3600; } } else if (arr[0] == "0" && now.Second == 0) { addtime = 60; } now = now.AddSeconds(addtime); } } catch { return null; } } ////// Cron表达式转换（自定义开始时间） /// /// 表达式 /// 开始时间 ///最近要执行的时间字符串 public static string GetNextDateTime(string cron, DateTime now) { try { string[] arr = cron.Split(' '); if (IsOrNoOne(cron)) { string date = arr[6] + "/" + arr[4] + "/" + arr[3] + " " + arr[2] + ":" + arr[1] + ":" + arr[0]; if(DateTime.Compare(Convert.ToDateTime(date),now)>0) { return date; } else { return null; } } Cron c = new Cron(); Seconds(c, arr[0]); Minutes(c, arr[1]); Hours(c, arr[2]); Month(c, arr[4]); if (arr.Length < 7) { Year(c, null); } else { Year(c, arr[6]); } int addtime = 1; while (true) { if (c.Seconds[now.Second] == 1 && c.Minutes[now.Minute] == 1 && c.Hours[now.Hour] == 1 && c.Month[now.Month - 1] == 1 && c.Year[now.Year - 2019] == 1) { if (arr[3] != "?") { Days(c, arr[3], DateTime.DaysInMonth(now.Year, now.Month), now); int DayOfWeek = (((int)now.DayOfWeek) + 6) % 7; if (c.Days[now.Day - 1] == 1 && c.Weeks[DayOfWeek] == 1) { return now.ToString("yyyy/MM/dd HH:mm:ss"); } } else { Weeks(c, arr[5], DateTime.DaysInMonth(now.Year, now.Month), now); int DayOfWeek = (((int)now.DayOfWeek) + 6) % 7; if (c.Days[now.Day - 1] == 1 && c.Weeks[DayOfWeek] == 1) { return now.ToString("yyyy/MM/dd HH:mm:ss"); } } } c.Init(); if (!arr[1].Contains('-') && !arr[1].Contains(',') && !arr[1].Contains('*') && !arr[1].Contains('/')) { if (now.Minute == int.Parse(arr[1])) { addtime = 3600; } } else if (arr[0] == "0" && now.Second == 0) { addtime = 60; } now = now.AddSeconds(addtime); } } catch { return null; } } ////// Cron表达式转换成中文描述 /// /// ///public static string TranslateToChinese(string cronExp) { if (cronExp == null || cronExp.Length < 1) { return "cron表达式为空"; } string[] tmpCorns = cronExp.Split(" "); StringBuilder sBuffer = new StringBuilder(); if (tmpCorns.Length == 6) { //解析月 if (!tmpCorns[4].Equals("*")) { sBuffer.Append(tmpCorns[4]).Append("月"); } else { sBuffer.Append("每月"); } //解析周 if (!tmpCorns[5].Equals("*") && !tmpCorns[5].Equals("?")) { char[] tmpArray = tmpCorns[5].ToCharArray(); foreach (char tmp in tmpArray) { switch (tmp) { case '1': sBuffer.Append("星期天"); break; case '2': sBuffer.Append("星期一"); break; case '3': sBuffer.Append("星期二"); break; case '4': sBuffer.Append("星期三"); break; case '5': sBuffer.Append("星期四"); break; case '6': sBuffer.Append("星期五"); break; case '7': sBuffer.Append("星期六"); break; case '-': sBuffer.Append("至"); break; default: sBuffer.Append(tmp); break; } } } //解析日 if (!tmpCorns[3].Equals("?")) { if (!tmpCorns[3].Equals("*")) { sBuffer.Append(tmpCorns[3]).Append("日"); } else { sBuffer.Append("每日"); } } //解析时 if (!tmpCorns[2].Equals("*")) { sBuffer.Append(tmpCorns[2]).Append("时"); } else { sBuffer.Append("每时"); } //解析分 if (!tmpCorns[1].Equals("*")) { sBuffer.Append(tmpCorns[1]).Append("分"); } else { sBuffer.Append("每分"); } //解析秒 if (!tmpCorns[0].Equals("*")) { sBuffer.Append(tmpCorns[0]).Append("秒"); } else { sBuffer.Append("每秒"); } } return sBuffer.ToString(); } #region 初始化Cron对象 private static void Seconds(Cron c, string str) { if (str == "*") { for (int i = 0; i < 60; i++) { c.Seconds[i] = 1; } } else if (str.Contains('-')) { int begin = int.Parse(str.Split('-')[0]); int end = int.Parse(str.Split('-')[1]); for (int i = begin; i <= end; i++) { c.Seconds[i] = 1; } } else if (str.Contains('/')) { int begin = int.Parse(str.Split('/')[0]); int interval = int.Parse(str.Split('/')[1]); while (true) { c.Seconds[begin] = 1; if ((begin + interval) >= 60) break; begin += interval; } } else if (str.Contains(',')) { for (int i = 0; i < str.Split(',').Length; i++) { c.Seconds[int.Parse(str.Split(',')[i])] = 1; } } else { c.Seconds[int.Parse(str)] = 1; } } private static void Minutes(Cron c, string str) { if (str == "*") { for (int i = 0; i < 60; i++) { c.Minutes[i] = 1; } } else if (str.Contains('-')) { int begin = int.Parse(str.Split('-')[0]); int end = int.Parse(str.Split('-')[1]); for (int i = begin; i <= end; i++) { c.Minutes[i] = 1; } } else if (str.Contains('/')) { int begin = int.Parse(str.Split('/')[0]); int interval = int.Parse(str.Split('/')[1]); while (true) { c.Minutes[begin] = 1; if ((begin + interval) >= 60) break; begin += interval; } } else if (str.Contains(',')) { for (int i = 0; i < str.Split(',').Length; i++) { c.Minutes[int.Parse(str.Split(',')[i])] = 1; } } else { c.Minutes[int.Parse(str)] = 1; } } private static void Hours(Cron c, string str) { if (str == "*") { for (int i = 0; i < 24; i++) { c.Hours[i] = 1; } } else if (str.Contains('-')) { int begin = int.Parse(str.Split('-')[0]); int end = int.Parse(str.Split('-')[1]); for (int i = begin; i <= end; i++) { c.Hours[i] = 1; } } else if (str.Contains('/')) { int begin = int.Parse(str.Split('/')[0]); int interval = int.Parse(str.Split('/')[1]); while (true) { c.Hours[begin] = 1; if ((begin + interval) >= 24) break; begin += interval; } } else if (str.Contains(',')) { for (int i = 0; i < str.Split(',').Length; i++) { c.Hours[int.Parse(str.Split(',')[i])] = 1; } } else { c.Hours[int.Parse(str)] = 1; } } private static void Month(Cron c, string str) { if (str == "*") { for (int i = 0; i < 12; i++) { c.Month[i] = 1; } } else if (str.Contains('-')) { int begin = int.Parse(str.Split('-')[0]); int end = int.Parse(str.Split('-')[1]); for (int i = begin; i <= end; i++) { c.Month[i - 1] = 1; } } else if (str.Contains('/')) { int begin = int.Parse(str.Split('/')[0]); int interval = int.Parse(str.Split('/')[1]); while (true) { c.Month[begin - 1] = 1; if ((begin + interval) >= 12) break; begin += interval; } } else if (str.Contains(',')) { for (int i = 0; i < str.Split(',').Length; i++) { c.Month[int.Parse(str.Split(',')[i]) - 1] = 1; } } else { c.Month[int.Parse(str) - 1] = 1; } } private static void Year(Cron c, string str) { if (str == null || str == "*") { for (int i = 0; i < 80; i++) { c.Year[i] = 1; } } else if (str.Contains('-')) { int begin = int.Parse(str.Split('-')[0]); int end = int.Parse(str.Split('-')[1]); for (int i = begin - 2019; i <= end - 2019; i++) { c.Year[i] = 1; } } else { c.Year[int.Parse(str) - 2019] = 1; } } private static void Days(Cron c, string str, int len, DateTime now) { for (int i = 0; i < 7; i++) { c.Weeks[i] = 1; } if (str == "*" || str == "?") { for (int i = 0; i < len; i++) { c.Days[i] = 1; } } else if (str.Contains('-')) { int begin = int.Parse(str.Split('-')[0]); int end = int.Parse(str.Split('-')[1]); for (int i = begin; i <= end; i++) { c.Days[i - 1] = 1; } } else if (str.Contains('/')) { int begin = int.Parse(str.Split('/')[0]); int interval = int.Parse(str.Split('/')[1]); while (true) { c.Days[begin - 1] = 1; if ((begin + interval) >= len) break; begin += interval; } } else if (str.Contains(',')) { for (int i = 0; i < str.Split(',').Length; i++) { c.Days[int.Parse(str.Split(',')[i]) - 1] = 1; } } else if (str.Contains('L')) { int i = str.Replace("L", "") == "" ? 0 : int.Parse(str.Replace("L", "")); c.Days[len - 1 - i] = 1; } else if (str.Contains('W')) { c.Days[len - 1] = 1; } else { c.Days[int.Parse(str) - 1] = 1; } } private static void Weeks(Cron c, string str, int len, DateTime now) { if (str == "*" || str == "?") { for (int i = 0; i < 7; i++) { c.Weeks[i] = 1; } } else if (str.Contains('-')) { int begin = int.Parse(str.Split('-')[0]); int end = int.Parse(str.Split('-')[1]); for (int i = begin; i <= end; i++) { c.Weeks[i - 1] = 1; } } else if (str.Contains(',')) { for (int i = 0; i < str.Split(',').Length; i++) { c.Weeks[int.Parse(str.Split(',')[i]) - 1] = 1; } } else if (str.Contains('L')) { int i = str.Replace("L", "") == "" ? 0 : int.Parse(str.Replace("L", "")); if (i == 0) { c.Weeks[6] = 1; } else { c.Weeks[i - 1] = 1; c.Days[GetLastWeek(i, now) - 1] = 1; return; } } else if (str.Contains('#')) { int i = int.Parse(str.Split('#')[0]); int j = int.Parse(str.Split('#')[1]); c.Weeks[i - 1] = 1; c.Days[GetWeek(i - 1, j, now)] = 1; return; } else { c.Weeks[int.Parse(str) - 1] = 1; } //week中初始化day，则说明day没要求 for (int i = 0; i < len; i++) { c.Days[i] = 1; } } #endregion #region 方法 public static bool IsOrNoOne(string cron) { if (cron.Contains('-') || cron.Contains(',') || cron.Contains('/') || cron.Contains('*')) { return false; } else { return true; } } /// /// 获取最后一个星期几的day /// /// 星期几 /// ///private static int GetLastWeek(int i, DateTime now) { DateTime d = now.AddDays(1 - now.Day).Date.AddMonths(1).AddSeconds(-1); int DayOfWeek = ((((int)d.DayOfWeek) + 6) % 7) + 1; int a = DayOfWeek >= i ? DayOfWeek - i : 7 + DayOfWeek - i; return DateTime.DaysInMonth(now.Year, now.Month) - a; } /// /// 获取当月第几个星期几的day /// /// 星期几 /// 第几周 /// ///public static int GetWeek(int i, int j, DateTime now) { int day = 0; DateTime d = new DateTime(now.Year, now.Month, 1); int DayOfWeek = ((((int)d.DayOfWeek) + 6) % 7) + 1; if (i >= DayOfWeek) { day = (7 - DayOfWeek + 1) + 7 * (j - 2) + i; } else { day = (7 - DayOfWeek + 1) + 7 * (j - 1) + i; } return day; } #endregion }
string cron="0 15 10 * * ?"; CronHelp.GetNextDateTime(cron, DateTime.Now); CronHelp.CronToDateTime(cron, DateTime.Now); CronHelp.CronToDateTime(cron);
