C# ToUniversalTime 으로 사용하기 – C# (Csharp) 프로그래밍

추천 : ToUniversalTime


 static void Main(string[] args)
        {
            string DepartureTime = "2023-09-09T11:40:00.000+08:00";

            string sDiffOfDatesTime = string.Empty;

            try
            {
                DateTime Today = DateTime.Now.ToUniversalTime();

                DateTime DepDate = DateTime.Parse(DepartureTime).ToUniversalTime();

                var diffOfDates = DepDate.Subtract(Today);

                if (diffOfDates.Days > 0)
                {
                    sDiffOfDatesTime = diffOfDates.Days + "D";
                }
                else
                {
                    sDiffOfDatesTime = diffOfDates.Hours + "H";
                }

            }
            catch
            {
                sDiffOfDatesTime = "";
            }

            Console.WriteLine(sDiffOfDatesTime);

            Console.ReadLine();

        }

static void Main(string[] args)

{

string DepartureTime = "2023-09-09T11:40:00.000+08:00";

string sDiffOfDatesTime = string.Empty;

try

{

DateTime Today = DateTime.Now.ToUniversalTime();

DateTime DepDate = DateTime.Parse(DepartureTime).ToUniversalTime();

var diffOfDates = DepDate.Subtract(Today);

if (diffOfDates.Days > 0)

{

sDiffOfDatesTime = diffOfDates.Days + "D";

}

else

{

sDiffOfDatesTime = diffOfDates.Hours + "H";

}

catch

{

sDiffOfDatesTime = "";

}

Console.WriteLine(sDiffOfDatesTime);

Console.ReadLine();

}


static void Main(string[] args)
        {   
            //1. 그 시간의 타임존 ID 를  구한다. 
            //2. 시간을 타임존 시간으로 변경
            //3. 차이 만큼의 시간을 구한다.

            string DepartureTime = "2023-09-09T11:40:00.000+08:00";

            string reg = @".000([-+]{1}[0-9]{2}:[0-9]{2})";
            var rx = new Regex(reg, RegexOptions.None);
            var matches = rx.Matches(DepartureTime);

            if (matches.Count > 0)
            {
                string offset = matches[0].Groups[1].ToString();

                TimeSpan ts = TimeSpan.Parse(offset.Replace('+',' ').Trim());
                var sBaseUtcOffset = TimeZoneInfo.GetSystemTimeZones().FirstOrDefault(x => x.BaseUtcOffset == ts);  //+07:00 로 시간대 id 추출

                DateTime cstTime = TimeZoneInfo.ConvertTimeBySystemTimeZoneId(DateTime.Now, sBaseUtcOffset.Id.ToString()); //현재 시간을 =>  시간대로 수정 

                Console.WriteLine(cstTime);
            }

            Console.ReadLine();

        }

static void Main(string[] args)

{

//1. 그 시간의 타임존 ID 를 구한다.

//2. 시간을 타임존 시간으로 변경

//3. 차이 만큼의 시간을 구한다.

string DepartureTime = "2023-09-09T11:40:00.000+08:00";

string reg = @".000([-+]{1}[0-9]{2}:[0-9]{2})";

var rx = new Regex(reg, RegexOptions.None);

var matches = rx.Matches(DepartureTime);

if (matches.Count > 0)

{

string offset = matches[0].Groups[1].ToString();

TimeSpan ts = TimeSpan.Parse(offset.Replace('+',' ').Trim());

var sBaseUtcOffset = TimeZoneInfo.GetSystemTimeZones().FirstOrDefault(x => x.BaseUtcOffset == ts); //+07:00 로 시간대 id 추출

DateTime cstTime = TimeZoneInfo.ConvertTimeBySystemTimeZoneId(DateTime.Now, sBaseUtcOffset.Id.ToString()); //현재 시간을 => 시간대로 수정

Console.WriteLine(cstTime);

}

Console.ReadLine();

}

using System.Linq;
using System.Text;
using System.Collections.ObjectModel;

namespace ConsoleTime
{
    class Program
    {
        static void Main(string[] args)
        {

            DateTime thisDate = new DateTime(2007, 3, 10, 0, 0, 0);
            DateTime dstDate = new DateTime(2007, 6, 10, 0, 0, 0);
            DateTimeOffset thisTime;

            thisTime = new DateTimeOffset(dstDate, new TimeSpan(-7, 0, 0));
            ShowPossibleTimeZones(thisTime);

            thisTime = new DateTimeOffset(thisDate, new TimeSpan(-6, 0, 0));
            
            ShowPossibleTimeZones(thisTime);

            thisTime = new DateTimeOffset(thisDate, new TimeSpan(+1, 0, 0));
            ShowPossibleTimeZones(thisTime);

            Console.ReadLine();
        }

        private static void ShowPossibleTimeZones(DateTimeOffset offsetTime)
        {
            TimeSpan offset = offsetTime.Offset;
            ReadOnlyCollection<TimeZoneInfo> timeZones;

            Console.WriteLine("{0} could belong to the following time zones:",
                              offsetTime.ToString());
            // Get all time zones defined on local system
            timeZones = TimeZoneInfo.GetSystemTimeZones();
            // Iterate time zones 
            foreach (TimeZoneInfo timeZone in timeZones)
            {
                // Compare offset with offset for that date in that time zone
                if (timeZone.GetUtcOffset(offsetTime.DateTime).Equals(offset))
                    Console.WriteLine("   {0}", timeZone.DisplayName);
            }
            Console.WriteLine();
        }
    }
}

결과

참조 : https://stackoverflow.com/questions/1201378/how-does-datetime-touniversaltime-work