c# - 如何将 Paypal 的 HH :MM:SS DD Mmm(. ) YYYY PST/PDT 转换为 C# UTC DateTime？

Question

我想在 SQL Server 数据库中以这种格式记录 payment_date。

更新。本能是正确的。在这里找到解决方案:http://www.codeillustrator.com/2010/03/converting-paypal-paymentdate-to-net.html ，验证...当然，如果 Paypal 搬出西海岸，我就会有麻烦了。有没有更好的方法来解析这个？也许与 TimeZone 一起？

public static DateTime ConvertPayPalDateTime(string payPalDateTime)
{
    // accept a few different date formats because of PST/PDT timezone and slight month difference in sandbox vs. prod.
    string[] dateFormats = { "HH:mm:ss MMM dd, yyyy PST", "HH:mm:ss MMM. dd, yyyy PST", "HH:mm:ss MMM dd, yyyy PDT", "HH:mm:ss MMM. dd, yyyy PDT" };
    DateTime outputDateTime;

    DateTime.TryParseExact(payPalDateTime, dateFormats, new CultureInfo("en-US"), DateTimeStyles.None, out outputDateTime);

    // convert to local timezone
    outputDateTime = outputDateTime.AddHours(3);

    return outputDateTime;
}

等一下，上面的代码对我来说是完全错误的。我在西海岸!理想情况下，这应该被更新以将日期发送到正确的 UTC DateTime 并处理任何时区。此外，上面的代码无法正确处理 PDT(如果转换为 UTC)。

Update2. 显然，至少在以前的版本中，沙盒会返回“Feb”。而直播返回“Feb”。哈哈。快来救救我吧!

Update3. Regex 版本链接 http://www.ifinity.com.au/Blog/EntryId/77/Converting-PayPal-Dates-to-Net-DateTime-using-Regex ，但调试可能是个问题。正则表达式似乎不是执行此操作的正确方法。一定有更好的方法。

/// <summary>
/// Converts a PayPal datestring into a valid .net datetime value
/// </summary>
/// <param name="dateValue">a string containing a PayPal date</param>
/// <param name="localUtcOffset">the number of hours from UTC/GMT the local 
/// time is (ie, the timezone where the computer is)</param>
/// <returns>Valid DateTime value if successful, DateTime.MinDate if not</returns>
private static DateTime ConvertFromPayPalDate(string rawPayPalDate, int localUtcOffset)
{
    /* regex pattern splits paypal date into
     * time : hh:mm:ss
     * date : Mmm dd yyyy
     * timezone : PST/PDT
     */
     const string payPalDateRegex = @"(?<time>\d{1,2}:\d{2}:\d{2})\s(?<date>(?<
Mmm>[A-Za-z\.]{3,5})\s(?<dd>\d{1,2}),?\s(?<yyyy>\d{4}))\s(?<tz>[A-Z]{0,3})";  
    //!important : above line broken over two lines for formatting - rejoin in code editor
    //example 05:49:56 Oct. 18, 2009 PDT
    //        20:48:22 Dec 25, 2009 PST
    Match dateMatch = Regex.Match(rawPayPalDate, payPalDateRegex, RegexOptions.IgnoreCase);
    DateTime time, date = DateTime.MinValue;
    //check to see if the regex pattern matched the supplied string
    if (dateMatch.Success)
    {
        //extract the relevant parts of the date from regex match groups
        string rawDate = dateMatch.Groups["date"].Value;
        string rawTime = dateMatch.Groups["time"].Value;
        string tz = dateMatch.Groups["tz"].Value;

        //create date and time values
        if (DateTime.TryParse(rawTime, out time) && DateTime.TryParse(rawDate, out date))
        {
            //add the time to the date value to get the datetime value
            date = date.Add(new TimeSpan(time.Hour, time.Minute, time.Second));
            //adjust for the pdt timezone.  Pass 0 to localUtcOffset to get UTC/GMT
            int offset = localUtcOffset + 7; //pdt = utc-7, pst = utc-8
            if (tz == "PDT")//pacific daylight time
                date = date.AddHours(offset);
            else  //pacific standard time
                date = date.AddHours(offset + 1);
        }
    }
    return date;
}

Answer 1

自 2006 年以来我就没有使用过任何 C#，因此这段代码可能无法编译。起飞前测试一下!

public static DateTime ConvertPayPalDateTime(string payPalDateTime)
{
  // Get the offset.
  // If C# supports switching on strings, it's probably more sensible to do that.
  int offset;
  if (payPalDateTime.EndsWith(" PDT"))
  {
     offset = 7;
  }
  else if (payPalDateTime.EndsWith(" PST"))
  {
     offset = 8;
  }
  else
  {
    throw some exception;
  }

  // We've "parsed" the time zone, so remove it from the string.
  payPalDatetime = payPalDateTime.Substring(0,payPalDateTime.Length-4);

  // Same formats as above, but with PST/PDT removed.
  string[] dateFormats = { "HH:mm:ss MMM dd, yyyy", "HH:mm:ss MMM. dd, yyyy" };

  // Parse the date. Throw an exception if it fails.
  DateTime ret = DateTime.ParseExact(payPalDateTime, dateFormats, new CultureInfo("en-US"), DateTimeStyles.None, out outputDateTime);

  // Add the offset, and make it a universal time.
  return ret.AddHours(offset).SpecifyKind(DateTimeKind.Universal);
}