使用 PST/CEST/UTC/etc 形式的時區解析 DateTime

Question

我正在嘗試解析類似於以下內容的國際日期時間字符串：

24-okt-08 21:09:06 CEST

到目前為止，我有類似的東西：

CultureInfo culture = CultureInfo.CreateSpecificCulture("nl-BE");
DateTime dt = DateTime.ParseExact("24-okt-08 21:09:06 CEST",
    "dd-MMM-yy HH:mm:ss ...", culture);

問題是我應該對格式字符串中的 '...' 使用什么？ 查看自定義日期和時間格式字符串MSDN 頁面似乎沒有列出用於解析 PST/CEST/GMT/UTC 格式的時區的格式字符串。

Answer 1

AFAIK 無法識別時區縮寫。 但是，如果您將縮寫替換為時區偏移量，就可以了。 例如：

DateTime dt1 = DateTime.ParseExact("24-okt-08 21:09:06 CEST".Replace("CEST", "+2"), "dd-MMM-yy HH:mm:ss z", culture);
DateTime dt2 = DateTime.ParseExact("24-okt-08 21:09:06 CEST".Replace("CEST", "+02"), "dd-MMM-yy HH:mm:ss zz", culture);
DateTime dt3 = DateTime.ParseExact("24-okt-08 21:09:06 CEST".Replace("CEST", "+02:00"), "dd-MMM-yy HH:mm:ss zzz", culture);

Answer 2

快速回答是，你不能這樣做。

---

這就是為什么，

有一個世界時區的權威數據庫，您可以從IANA獲取它在這里。

問題是，3 或 4 個字母的縮寫與 IANA 時區是多對一的關聯。 例如， "AMT"意味着不同的東西，這取決於您的文化、您所在的世界的哪個部分以及您的應用程序的上下文。

AMT "Armenia Time" Asia          UTC + 4 hours 
AMT "Amazon Time"  South America UTC - 4 hours 

如果你真的想解決這個問題，我建議使用Noda Time來表示你的Instance 。 您必須編寫一些代碼才能將縮寫轉換為標准 IANA 時區。

我們無法為您執行此操作，這取決於您的應用程序上下文。

---

另一個很好的例子是"CST" 。

CST "China Standard Time"   Asia            UTC + 8 hours 
CST "Central Standard Time" Central America UTC - 6 hours 
CST "Cuba Standard Time"    Caribbean       UTC - 5 hours 
CST "Central Standard Time" North America   UTC - 6 hours 

Answer 3

如果您決定走搜索和替換路線（我做到了），請使用縮寫字典。

Dictionary<string, string> _timeZones = new Dictionary<string, string>() {
            {"ACDT", "+1030"},
            {"ACST", "+0930"},
            {"ADT", "-0300"},
            {"AEDT", "+1100"},
            {"AEST", "+1000"},
            {"AHDT", "-0900"},
            {"AHST", "-1000"},
            {"AST", "-0400"},
            {"AT", "-0200"},
            {"AWDT", "+0900"},
            {"AWST", "+0800"},
            {"BAT", "+0300"},
            {"BDST", "+0200"},
            {"BET", "-1100"},
            {"BST", "-0300"},
            {"BT", "+0300"},
            {"BZT2", "-0300"},
            {"CADT", "+1030"},
            {"CAST", "+0930"},
            {"CAT", "-1000"},
            {"CCT", "+0800"},
            {"CDT", "-0500"},
            {"CED", "+0200"},
            {"CET", "+0100"},
            {"CEST", "+0200"},
            {"CST", "-0600"},
            {"EAST", "+1000"},
            {"EDT", "-0400"},
            {"EED", "+0300"},
            {"EET", "+0200"},
            {"EEST", "+0300"},
            {"EST", "-0500"},
            {"FST", "+0200"},
            {"FWT", "+0100"},
            {"GMT", "GMT"},
            {"GST", "+1000"},
            {"HDT", "-0900"},
            {"HST", "-1000"},
            {"IDLE", "+1200"},
            {"IDLW", "-1200"},
            {"IST", "+0530"},
            {"IT", "+0330"},
            {"JST", "+0900"},
            {"JT", "+0700"},
            {"MDT", "-0600"},
            {"MED", "+0200"},
            {"MET", "+0100"},
            {"MEST", "+0200"},
            {"MEWT", "+0100"},
            {"MST", "-0700"},
            {"MT", "+0800"},
            {"NDT", "-0230"},
            {"NFT", "-0330"},
            {"NT", "-1100"},
            {"NST", "+0630"},
            {"NZ", "+1100"},
            {"NZST", "+1200"},
            {"NZDT", "+1300"},
            {"NZT", "+1200"},
            {"PDT", "-0700"},
            {"PST", "-0800"},
            {"ROK", "+0900"},
            {"SAD", "+1000"},
            {"SAST", "+0900"},
            {"SAT", "+0900"},
            {"SDT", "+1000"},
            {"SST", "+0200"},
            {"SWT", "+0100"},
            {"USZ3", "+0400"},
            {"USZ4", "+0500"},
            {"USZ5", "+0600"},
            {"USZ6", "+0700"},
            {"UT", "-0000"},
            {"UTC", "-0000"},
            {"UZ10", "+1100"},
            {"WAT", "-0100"},
            {"WET", "-0000"},
            {"WST", "+0800"},
            {"YDT", "-0800"},
            {"YST", "-0900"},
            {"ZP4", "+0400"},
            {"ZP5", "+0500"},
            {"ZP6", "+0600"}
        };

Answer 4

我有兩個答案，因為我不確定你在問什么。

1）我看到您正在使用 CultureInfo，因此如果您只想將日期和時間格式化為特定於文化的格式，我會將日期/時間和時區分開，在日期/時間上應用文化方法並附加時區。 如果不同文化的“CEST”不同，則必須通過列出所有選項（可能在案例陳述中）來更改它。

2) 如果您想將日期/時間轉換為另一個時區，則不能使用 CultureInfo，

我建議閱讀： http : //msdn.microsoft.com/en-us/library/ms973825.aspx

您還可以使用 .net 框架 3.5 類 TimeZoneInfo（與 TimeZone 不同）讓您的生活更輕松。

http://msdn.microsoft.com/en-us/library/system.timezoneinfo.aspx

Answer 5

這是如何：

1. 獲取字符串（前提：格式：ddd, dd MMM yyyy HH:mm:ss zzz）
2. 獲取最后一個空格
3. 從字符串中刪除 zzz，但保存 zzz 的值
4. zzz 的查找偏移量
5. 向字符串添加偏移量

string dateString = reader.ReadContentAsString(); int timeZonePos = dateString.LastIndexOf(' ') + 1; string tz = dateString.Substring(timeZonePos); dateString = dateString.Substring(0, dateString.Length - tz.Length ); dateString += s_timeZoneOffsets[tz]; // https://msdn.microsoft.com/en-us/library/w2sa9yss(v=vs.110).aspx //string es = reader.ReadElementString("pubDate"); this.m_value = System.DateTime.ParseExact(dateString, "ddd, dd MMM yyyy HH:mm zzz", System.Globalization.CultureInfo.InvariantCulture);

和

private static System.Collections.Generic.Dictionary<string, string> s_timeZoneOffsets =
    new System.Collections.Generic.Dictionary<string, string>() {
    {"ACDT", "+10:30"},
    {"ACST", "+09:30"},
    {"ADT", "-03:00"},
    {"AEDT", "+11:00"},
    {"AEST", "+10:00"},
    {"AHDT", "-09:00"},
    {"AHST", "-10:00"},
    {"AST", "-04:00"},
    {"AT", "-02:00"},
    {"AWDT", "+09:00"},
    {"AWST", "+08:00"},
    {"BAT", "+03:00"},
    {"BDST", "+02:00"},
    {"BET", "-11:00"},
    {"BST", "-03:00"},
    {"BT", "+03:00"},
    {"BZT2", "-03:00"},
    {"CADT", "+10:30"},
    {"CAST", "+09:30"},
    {"CAT", "-10:00"},
    {"CCT", "+08:00"},
    {"CDT", "-05:00"},
    {"CED", "+02:00"},
    {"CET", "+01:00"},
    {"CEST", "+02:00"},
    {"CST", "-06:00"},
    {"EAST", "+10:00"},
    {"EDT", "-04:00"},
    {"EED", "+03:00"},
    {"EET", "+02:00"},
    {"EEST", "+03:00"},
    {"EST", "-05:00"},
    {"FST", "+02:00"},
    {"FWT", "+01:00"},
    {"GMT", "+00:00"},
    {"GST", "+10:00"},
    {"HDT", "-09:00"},
    {"HST", "-10:00"},
    {"IDLE", "+12:00"},
    {"IDLW", "-12:00"},
    {"IST", "+05:30"},
    {"IT", "+03:30"},
    {"JST", "+09:00"},
    {"JT", "+07:00"},
    {"MDT", "-06:00"},
    {"MED", "+02:00"},
    {"MET", "+01:00"},
    {"MEST", "+02:00"},
    {"MEWT", "+01:00"},
    {"MST", "-07:00"},
    {"MT", "+08:00"},
    {"NDT", "-02:30"},
    {"NFT", "-03:30"},
    {"NT", "-11:00"},
    {"NST", "+06:30"},
    {"NZ", "+11:00"},
    {"NZST", "+12:00"},
    {"NZDT", "+13:00"},
    {"NZT", "+12:00"},
    {"PDT", "-07:00"},
    {"PST", "-08:00"},
    {"ROK", "+09:00"},
    {"SAD", "+10:00"},
    {"SAST", "+09:00"},
    {"SAT", "+09:00"},
    {"SDT", "+10:00"},
    {"SST", "+02:00"},
    {"SWT", "+01:00"},
    {"USZ3", "+04:00"},
    {"USZ4", "+05:00"},
    {"USZ5", "+06:00"},
    {"USZ6", "+07:00"},
    {"UT", "-00:00"},
    {"UTC", "-00:00"},
    {"UZ10", "+11:00"},
    {"WAT", "-01:00"},
    {"WET", "-00:00"},
    {"WST", "+08:00"},
    {"YDT", "-08:00"},
    {"YST", "-09:00"},
    {"ZP4", "+04:00"},
    {"ZP5", "+05:00"},
    {"ZP6", "+06:00"}
};

Answer 6

這就是我必須做的。

我從 javascript 接收日期時間，然后將其傳遞給 ASP.NET 以存儲在 Oracle 數據庫中。 這是我的東部和中部時間的 C# 代碼。

string datetimevalue = hidfileDateTime.Value; 

datetimevalue= datetimevalue.Replace("EDT", "EST"); 
datetimevalue = datetimevalue.Replace("CDT", "CST");
if (datetimevalue.Contains("CST"))
{
    filedt = DateTime.ParseExact(datetimevalue, "ddd MMM d HH:mm:ss CST yyyy", provider).ToUniversalTime().AddHours(1).ToLocalTime();
}
else
{
    filedt = DateTime.ParseExact(datetimevalue, "ddd MMM d HH:mm:ss EST yyyy", provider);
}