c# DateTime (날짜, 시간, 요일 추출) Utils

Gps log Viewer을 만들면서 DateTime 객체를 가공하여 보여주는 경우가 많았다.

개발하면서 추가했던 Utils Method 들이다. 

https://learn.microsoft.com/ko-kr/dotnet/api/system.datetime?view=net-7.0 

DateTime 구조체 (System)

 public class DateTimeHelper
 {
     public enum TimeFormat
     {
         HH,
         HH_MM,
         HH_MM_SS,
         HH_MM_SS_MS,
         HHHH_MM_SS_MS
     }

     /// <summary>
     /// Time Format Enum
     /// </summary>
     public enum DateFormat
     {
         /// <summary>
         /// Local to UTC yyyy-MM-dd hh:mm:ss
         /// </summary>
         CONVERT_LOCAL_TO_UTC,

         /// <summary>
         /// UTC to LOCAL yyyyy-MM-dd hh:mm:ss
         /// </summary>
         CONVERT_UTC_TO_LOCAL,

         /// <summary>
         /// NOMAL(변경없음) yyyy-MM-dd hh:mm:ss
         /// </summary>
         CONVERT_NOMAL
     }

     /// <summary>
     /// Enum 값에 따라 시간 포맷을 리턴
     /// </summary>
     /// <param name="ts"></param>
     /// <param name="timeFormat"></param>
     /// <returns></returns>
     public static string GetTimeFormat(TimeSpan ts, TimeFormat timeFormat)
     {
         string result = string.Empty;

         switch (timeFormat)
         {
             case TimeFormat.HH:
                 result = string.Format("{0:00}", ts.Hours);
                 break;
             case TimeFormat.HH_MM:
                 result = string.Format("{0:00}:{1:00}", ts.Hours, ts.Minutes);
                 break;
             case TimeFormat.HH_MM_SS:
                 result = string.Format("{0:00}:{1:00}:{2:00}", ts.Hours, ts.Minutes, ts.Seconds);
                 break;
             case TimeFormat.HH_MM_SS_MS:
                 result = string.Format("{0:00}:{1:00}:{2:00}.{3:00}", ts.Hours, ts.Minutes, ts.Seconds, ts.Milliseconds / 10);
                 break;
             case TimeFormat.HHHH_MM_SS_MS:
                 result = string.Format("{0:0000}:{1:00}:{2:00}", ts.TotalHours, ts.Minutes, ts.Seconds);
                 break;
             default:
                 break;
         }

         return result;
     }

     /// <summary>
     /// 시간 계산
     /// </summary>
     /// <param name="startDate">시작시간</param>
     /// <param name="endDate">종료시간</param>
     /// <returns></returns>
     public static string GetDateTimeCalc(string startDate, string endDate)
     {
         string result = string.Empty;

         if (!string.IsNullOrWhiteSpace(startDate) && !string.IsNullOrWhiteSpace(endDate))
             result = GetTimeFormat(GetTimeSpan(startDate, endDate), TimeFormat.HH_MM_SS);
         else
             result = "00:00:00";
         return result;
     }

     /// <summary>
     /// 시간 간격
     /// </summary>
     /// <param name="startDate"></param>
     /// <param name="endDate"></param>
     /// <returns></returns>
     public static TimeSpan GetTimeSpan(string startDate, string endDate)
     {
         DateTime StartDate = Convert.ToDateTime(startDate.Substring(0, 19));
         DateTime EndDate = Convert.ToDateTime(endDate.Substring(0, 19));

         TimeSpan ts = EndDate - StartDate;

         return ts;
     }

     /// <summary>
     /// 현재시간 리턴
     /// </summary>
     /// <returns></returns>
     public static string GetDateTimeNow()
     {
         string now = DateTime.Now.ToString("yyyy-MM-dd hh:mm:ss fff");
         return now;
     }

     /// <summary>
     /// Utc <-> Local 변경
     /// </summary>
     /// <param name="df"></param>
     /// <param name="time"></param>
     /// <param name="timeType"></param>
     /// <param name="daySeq"></param>
     /// <returns></returns>
     public static string ConvertTimeTotime(DateFormat df, string time, string timeType, int daySeq)
     {
         string rtnTime = string.Empty;

         if (!string.IsNullOrWhiteSpace(time))
         {
             int year    = Convert.ToInt32(time.Substring(0, 4));   
             int month   = Convert.ToInt32(time.Substring(5, 2));   
             int day     = Convert.ToInt32(time.Substring(8, 2));   
             int hour    = Convert.ToInt32(time.Substring(11, 2));  
             int min     = Convert.ToInt32(time.Substring(14, 2));  
             int second  = Convert.ToInt32(time.Substring(17, 2));  

             DateTime date = new DateTime(year, month, day, hour, min, second);

             switch (df)
             {
                 case DateFormat.CONVERT_LOCAL_TO_UTC: // Local to UTC yyyy-MM-dd hh:mm:ss
                     rtnTime = TimeZoneInfo.ConvertTimeToUtc(date).ToString("yyyy-MM-dd HH:mm:ss");
                     break;
                 case DateFormat.CONVERT_UTC_TO_LOCAL: // UTC to Local yyyy-MM-dd hh:mm:ss
                     rtnTime = TimeZone.CurrentTimeZone.ToLocalTime(date).ToString("yyyy-MM-dd HH:mm:ss");
                     break;
                 case DateFormat.CONVERT_NOMAL: // NOMAL yyyyMMdd hhmmss
                     rtnTime = date.ToString("yyyy-MM-dd HH:mm:ss");
                     break;
             }
             if (timeType == "R")
                 rtnTime = rtnTime.Replace(" ", "T") + time.Substring(19);
             else if (timeType == "L")
                 rtnTime = rtnTime.Replace("T", " ").Substring(0, 19);
         }
         else
         {
             if (timeType == "R")
                 rtnTime = GetDateTimeNow();
             else if (timeType == "L")
                 rtnTime = Routing.GetNewLogDate(daySeq.ToString());
         }

         return rtnTime;
     }

     /// <summary>
     /// 이번주 시작일과 마지막날
     /// </summary>
     /// <returns></returns>
     //public static string GetCrrrentWeekDay(string day)
     //{
     //    string rtnWeekDay = string.Empty;
     //    System.Globalization.CultureInfo current = System.Threading.Thread.CurrentThread.CurrentCulture;

     //    //DateTime toDay = DateTime.Now.AddDays(dayCount);
     //    DateTime toDay = Convert.ToDateTime(day);

     //    DayOfWeek dwFirst = current.DateTimeFormat.FirstDayOfWeek;
     //    DayOfWeek dwToday = current.Calendar.GetDayOfWeek(toDay);

     //    int iDiff = dwToday - dwFirst;
     //    DateTime dtFirstDayofThisWeek = toDay.AddDays(-iDiff +1);
     //    DateTime dtLastDayofThisWeek = dtFirstDayofThisWeek.AddDays(6);

     //    rtnWeekDay = string.Format("{0}~{1}", dtFirstDayofThisWeek.ToString("yyyy-MM-dd"), dtLastDayofThisWeek.ToString("yyyy-MM-dd"));

     //    return rtnWeekDay;
     //}

     /// <summary>
     /// 이번주 시작일과 마지막날
     /// </summary>
     /// <returns></returns>
     public static string GetWeekDay(string day)
     {
         string rtnWeekDay = string.Empty;
         string firstDay = string.Empty;
         string lastDay = string.Empty;

         DateTime dt = Convert.ToDateTime(day);

         switch (WeekDayNum(day))
         {
             case 1:
                 firstDay = day;
                 lastDay = dt.AddDays(6).ToString("yyyy-MM-dd");
                 break;
             case 2:
                 firstDay = dt.AddDays(-1).ToString("yyyy-MM-dd");
                 lastDay = dt.AddDays(5).ToString("yyyy-MM-dd");
                 break;
             case 3:
                 firstDay = dt.AddDays(-2).ToString("yyyy-MM-dd");
                 lastDay = dt.AddDays(4).ToString("yyyy-MM-dd");
                 break;
             case 4:
                 firstDay = dt.AddDays(-3).ToString("yyyy-MM-dd");
                 lastDay = dt.AddDays(3).ToString("yyyy-MM-dd");
                 break;
             case 5:
                 firstDay = dt.AddDays(-4).ToString("yyyy-MM-dd");
                 lastDay = dt.AddDays(2).ToString("yyyy-MM-dd");
                 break;
             case 6:
                 firstDay = dt.AddDays(-5).ToString("yyyy-MM-dd");
                 lastDay = dt.AddDays(1).ToString("yyyy-MM-dd");
                 break;
             case 7:
                 firstDay = dt.AddDays(-6).ToString("yyyy-MM-dd");
                 lastDay = dt.AddDays(0).ToString("yyyy-MM-dd");
                 break;
         }

         rtnWeekDay = string.Format("{0}~{1}", firstDay, lastDay);
         return rtnWeekDay;
     }

     public static List<string> BetweenDay(string startDay, string EndDay)
     {
         List<string> listDay = new List<string>();

         DateTime fromDt = DateTime.Parse(startDay);
         DateTime toDt = DateTime.Parse(EndDay);

         int duration = DayCount(fromDt, toDt);

         for (int i = 0; i <= duration; i++)
         {
             listDay.Add(fromDt.AddDays(i).ToString("yyyy-MM-dd"));
         }

         return listDay;
     }

     static int DayCount(DateTime fromDt, DateTime ToDt)
     {
         TimeSpan ts = ToDt - fromDt;
         return ts.Days;
     }

     public static string WeekDay(string day)
     {
         string rtnWeekday = string.Empty;

         if (day.Equals("Total"))
             return "";

         DayOfWeek dt = Convert.ToDateTime(day).DayOfWeek;

         switch (dt)
         {
             case DayOfWeek.Monday: //월
                 rtnWeekday = "월";
                 break;

             case DayOfWeek.Tuesday: //화
                 rtnWeekday = "화";
                 break;

             case DayOfWeek.Wednesday: //수
                 rtnWeekday = "수";
                 break;

             case DayOfWeek.Thursday: //목
                 rtnWeekday = "목";
                 break;

             case DayOfWeek.Friday: //금
                 rtnWeekday = "금";
                 break;

             case DayOfWeek.Saturday: //토
                 rtnWeekday = "토";
                 break;

             case DayOfWeek.Sunday: //일
                 rtnWeekday = "일";
                 break;
         }

         return rtnWeekday;
     }

     public static int WeekDayNum(string day)
     {
         int rtnNum = 0;

         DayOfWeek dt = Convert.ToDateTime(day).DayOfWeek;

         switch (dt)
         {
             case DayOfWeek.Monday: //월
                 rtnNum = 1;
                 break;

             case DayOfWeek.Tuesday: //화
                 rtnNum = 2;
                 break;

             case DayOfWeek.Wednesday: //수
                 rtnNum = 3;
                 break;

             case DayOfWeek.Thursday: //목
                 rtnNum = 4;
                 break;

             case DayOfWeek.Friday: //금
                 rtnNum = 5;
                 break;

             case DayOfWeek.Saturday: //토
                 rtnNum = 6;
                 break;

             case DayOfWeek.Sunday: //일
                 rtnNum = 7;
                 break;
         }

         return rtnNum;
     }

     //현재일이 포함된 년중 주와 현재달의 첫째날의 년중 주를 구하여 차로서 해당일의 월간 주간을 알아낼수 있다.
     public static int GetCurrentWeekOfMonth(string date)
     {
         CultureInfo culture = new CultureInfo("ko-KR");

         // now = DateTime.Now;
         DateTime firstDayOfMonth = Convert.ToDateTime(date);
         int firstWeekOfMonth = GetWeekOfYear(firstDayOfMonth, culture);
         int nowWeekOfMonth = GetWeekOfYear(Convert.ToDateTime(date), culture);

         return (nowWeekOfMonth - firstWeekOfMonth) + 1;
     }

     public static int GetWeekOfYear(DateTime targetDate)
     {
         return GetWeekOfYear(targetDate, null);
     }

     // 주어진 날짜가 1년 중 몇 번째 주(week)인가를 반환한다.
     // 달력 규칙은 매개변수로 주어진 CultureInfo를 사용한다.
     public static int GetWeekOfYear(DateTime targetDate, CultureInfo culture)
     {
         if (culture == null)
         {
             culture = CultureInfo.CurrentCulture;
         }
         CalendarWeekRule weekRule = culture.DateTimeFormat.CalendarWeekRule;
         DayOfWeek firstDayOfWeek = culture.DateTimeFormat.FirstDayOfWeek;
         return culture.Calendar.GetWeekOfYear(targetDate, weekRule, firstDayOfWeek);
     }

     /// <summary>
     /// 달의 일요일만 추출
     /// </summary>
     /// <param name="date"></param>
     /// <returns></returns>
     public static List<string> getWeekdatesandDates(string date)
     {
         List<string> weekdays = new List<string>();

         string[] dates = date.Split('-');

         int year = Convert.ToInt32(dates[0]);
         int month = Convert.ToInt32(dates[1]);

         DateTime firstOfMonth = new DateTime(year, month, 1);

         DateTime currentDay = firstOfMonth;
         while (firstOfMonth.Month == currentDay.Month)
         {
             DayOfWeek dayOfWeek = currentDay.DayOfWeek;
             if (dayOfWeek == DayOfWeek.Sunday)
                 weekdays.Add(currentDay.Date.ToString("yyyy-MM-dd"));

             currentDay = currentDay.AddDays(1);
         }

         return weekdays;
     }
 }