我从另一台机器获得时区信息，格式为：
"CET-1CEST,M3.5.0/2,M10.5.0/3"
（Posix风格时区）
我需要解析它并将其转换为c# .net TimeZoneInfo class。
有办法做到这一点吗？
根据本文：http://www.ibm.com/developerworks/aix/library/au-aix-posix/POSIX时间，如"CST6CDT，M3.2.0/22:00:00，M11.1.0/22:0:00"，具有以下规范：
- CST6CDT是时区的名称
- CST是DST关闭时使用的缩写
- 与格林尼治标准时间相差6小时
- CDT是DST开启时使用的缩写
- ，M3为第三个月
- .2是该月中第二次出现的日期
- 0是星期日
- /时间是2:00
- ，M11是第十一个月
- .1是该月中第一次出现的日期
- 0是星期日
- /时间是2:00
日期为Mm.n.d格式，其中：
- Mm（1-12）12个月
- n（1-5）1表示月份的第一周，5表示月份的最后一周
- d（0-6）周日0，周六6
好吧，基于这些信息和TimeZoneInfo类中的调整规则，您可以使用以下代码进行转换：
public static TimeZoneInfo ConvertPosixToTimeZoneInfo(string posix)
{
string[] tokens = posix.Split(',');
tokens[0] = tokens[0].Replace("/", ".");
var match = Regex.Match(tokens[0], @"[-+]?[0-9]*.?[0-9]+").Value;
var ticks = (long)(decimal.Parse(match, CultureInfo.InvariantCulture) * 60) * 600000000;
var baseOffset = new TimeSpan(ticks);
var systemTimeZones = TimeZoneInfo.GetSystemTimeZones().Where(t => t.BaseUtcOffset == baseOffset).ToList();
var startRuleTokens = tokens[1].TrimStart('M').Split('/');
var startDateRuleTokens = startRuleTokens[0].Split('.');
var startTimeRuleTokens = startRuleTokens[1].Split(':');
var endRuleTokens = tokens[2].TrimStart('M').Split('/');
var endDateRuleTokens = endRuleTokens[0].Split('.');
var endTimeRuleTokens = endRuleTokens[1].Split(':');
int? targetIndex = null;
for (int i = 0; i < systemTimeZones.Count; i++)
{
var adjustmentRules = systemTimeZones[i].GetAdjustmentRules();
foreach (var rule in adjustmentRules)
{
if (rule.DaylightTransitionStart.Month == int.Parse(startDateRuleTokens[0]) &&
rule.DaylightTransitionStart.Week == int.Parse(startDateRuleTokens[1]) &&
rule.DaylightTransitionStart.DayOfWeek == (DayOfWeek)int.Parse(startDateRuleTokens[2]) &&
rule.DaylightTransitionStart.TimeOfDay.Hour == int.Parse(startTimeRuleTokens[0]) &&
rule.DaylightTransitionStart.TimeOfDay.Minute == int.Parse(startTimeRuleTokens[1]) &&
rule.DaylightTransitionStart.TimeOfDay.Second == int.Parse(startTimeRuleTokens[2]) &&
rule.DaylightTransitionEnd.Month == int.Parse(endDateRuleTokens[0]) &&
rule.DaylightTransitionEnd.Week == int.Parse(endDateRuleTokens[1]) &&
rule.DaylightTransitionEnd.DayOfWeek == (DayOfWeek)int.Parse(endDateRuleTokens[2]) &&
rule.DaylightTransitionEnd.TimeOfDay.Hour == int.Parse(endTimeRuleTokens[0]) &&
rule.DaylightTransitionEnd.TimeOfDay.Minute == int.Parse(endTimeRuleTokens[1]) &&
rule.DaylightTransitionEnd.TimeOfDay.Second == int.Parse(endTimeRuleTokens[2]))
{
targetIndex = i;
break;
}
}
}
if (targetIndex.HasValue)
return systemTimeZones[targetIndex.Value];
return null;
}
我会根据它的格式来解析它：http://www.ibm.com/developerworks/aix/library/au-aix-posix/
也许你也可以考虑：http://nodatime.org/-我目前不知道他们是否支持这一点。
下面的代码应该可以完成任务。
请记住，虽然这将为您提供一个有效的TimeZoneInfo对象，但它不会将信息映射到现有的Windows时区。您可以使用各种转换函数，如TimeZoneInfo.ConvertTime，但不要指望它神奇地知道PST8PDT应该与"Pacific Standard Time"对齐。
public static TimeZoneInfo PosixToTzi(string posixTz)
{
var parts = posixTz.Split(',');
var zoneparts = Regex.Split(parts[0], @"([0-9+-.]+)");
double baseOffsetHours;
if (zoneparts.Length > 1)
{
if (!Double.TryParse(zoneparts[1], out baseOffsetHours))
throw new FormatException();
}
else
{
// recognize RFC822 time zone abbreviations
switch (zoneparts[0].ToUpper())
{
case "UT":
case "UTC":
case "GMT":
baseOffsetHours = 0;
break;
case "EDT":
baseOffsetHours = 4;
break;
case "EST":
case "CDT":
baseOffsetHours = 5;
break;
case "CST":
case "MDT":
baseOffsetHours = 6;
break;
case "MST":
case "PDT":
baseOffsetHours = 7;
break;
case "PST":
baseOffsetHours = 8;
break;
default:
throw new FormatException();
}
}
double dstOffsetHours = baseOffsetHours - 1;
if (zoneparts.Length == 4)
{
if (!Double.TryParse(zoneparts[3], out dstOffsetHours))
throw new FormatException();
}
var baseOffset = TimeSpan.FromHours(-baseOffsetHours);
var dstDelta = TimeSpan.FromHours(baseOffsetHours - dstOffsetHours);
var rules = new List<TimeZoneInfo.AdjustmentRule>();
if (parts.Length == 3)
{
var rule = TimeZoneInfo.AdjustmentRule.CreateAdjustmentRule(
DateTime.MinValue.Date, DateTime.MaxValue.Date, dstDelta,
ParsePosixTransition(parts[1]), ParsePosixTransition(parts[2]));
rules.Add(rule);
}
return TimeZoneInfo.CreateCustomTimeZone(posixTz, baseOffset, parts[0], zoneparts[0],
zoneparts[zoneparts.Length == 3 ? 2 : 0], rules.ToArray());
}
private static TimeZoneInfo.TransitionTime ParsePosixTransition(string transition)
{
var parts = transition.Split('/');
if (parts.Length > 2)
throw new FormatException();
double hours = 0;
if (parts.Length == 2)
{
if (!Double.TryParse(parts[1], out hours))
throw new FormatException();
}
var time = DateTime.MinValue.AddHours(hours);
if (transition.StartsWith("M", StringComparison.OrdinalIgnoreCase))
{
var dateParts = parts[0].Substring(1).Split('.');
if (dateParts.Length > 3)
throw new FormatException();
int month;
if (!Int32.TryParse(dateParts[0], out month))
throw new FormatException();
int week;
if (!Int32.TryParse(dateParts[1], out week))
throw new FormatException();
int dow;
if (!Int32.TryParse(dateParts[2], out dow))
throw new FormatException();
return TimeZoneInfo.TransitionTime.CreateFloatingDateRule(time, month, week, (DayOfWeek) dow);
}
if (transition.StartsWith("J", StringComparison.OrdinalIgnoreCase))
{
int dayNum;
if (!Int32.TryParse(parts[0].Substring(1), out dayNum))
throw new FormatException();
var date = DateTime.MinValue.AddDays(dayNum);
return TimeZoneInfo.TransitionTime.CreateFixedDateRule(time, date.Month, date.Day);
}
throw new FormatException();
}