C# 给定DateTime对象,如何获取字符串格式的ISO 8601日期?
鉴于: 如何获取以兼容格式表示相同值的字符串 请注意,ISO 8601定义了许多类似的格式。我正在寻找的具体格式是:C# 给定DateTime对象,如何获取字符串格式的ISO 8601日期?,c#,datetime,datetime-format,iso8601,C#,Datetime,Datetime Format,Iso8601,鉴于: 如何获取以兼容格式表示相同值的字符串 请注意,ISO 8601定义了许多类似的格式。我正在寻找的具体格式是: DateTime.UtcNow 返回类似于2008-04-10T06:30:00的内容 UtcNow显然会返回一个时间,因此在以下方面没有任何危害: DateTime.UtcNow.ToString("s") 读者注意:一些评论者指出了这个答案中的一些问题(特别是与第一个建议有关)。有关更多信息,请参阅评论部分 这将为您提供类似于2008-09-22T13:57:31.231
DateTime.UtcNow
返回类似于2008-04-10T06:30:00的内容
UtcNow
显然会返回一个时间,因此在以下方面没有任何危害:
DateTime.UtcNow.ToString("s")
读者注意:一些评论者指出了这个答案中的一些问题(特别是与第一个建议有关)。有关更多信息,请参阅评论部分
这将为您提供类似于2008-09-22T13:57:31.2311892-04:00的日期
另一种方式是:
DateTime.UtcNow.ToString("yyyy-MM-ddTHH\\:mm\\:ss.fffffffzzz");
这给了你2008-09-22T14:01:54.9571247Z
要获取指定的格式,可以使用:
DateTime.UtcNow.ToString("o");
DateTime.UtcNow.ToString(“s”,System.Globalization.CultureInfo.InvariantCulture)
应该为您提供所需的内容,因为“s”格式说明符被描述为可排序的日期/时间模式;符合ISO 8601
编辑:要根据OP的要求在末尾获得额外的
Z
,请使用“o”
而不是“s”将DateTime.UtcNow转换为yyyy-MM ddTHH:MM:ssZ的字符串表示形式,您可以使用带有自定义格式字符串的DateTime结构的ToString()方法。使用带有日期时间的自定义格式字符串时,请务必记住,需要使用单引号转义分隔符
以下内容将返回所需的字符串表示:
DateTime.UtcNow.ToString("yyyy-MM-ddTHH:mm:ssZ")
我只想使用:
它将自动保留时区
标准格式说明符表示由属性定义的自定义日期和时间格式字符串。该模式反映定义的标准(ISO 8601),并且该属性是只读的。因此,无论所使用的区域性或提供的格式提供程序如何,它都是相同的。自定义格式字符串是“yyyy”-“MM”-“dd'T'HH”:“MM”:“ss”
使用此标准格式说明符时,格式化或解析操作始终使用不变区域性
–从使用:
XmlConvert.ToString(DateTime.UtcNow, XmlDateTimeSerializationMode.RoundtripKind);
资料来源:
- (MSDN)
- (MSDN)
如果您的开发级别低于或高于此级别,则可以使用
UTC
strUtcTime_o: 2012-09-17T22:02:51.4021600Z
strUtcTime_s: 2012-09-17T22:02:51
strUtcTime_custom: 2012-09-17T22:02:51Z
Local Time
strLocalTimeAndOffset_o: 2012-09-17T15:02:51.4021600-07:00
strLocalTimeAndOffset_s: 2012-09-17T15:02:51
strLocalTimeAndOffset_custom: 2012-09-17T22:02:51Z
=>
您可以通过以下代码获得“Z”(UTC):
val it : string = "2013-10-13T13:03:50.2950037Z"
原因如下:
ISO 8601有一些不同的格式:
DateTimeKind.Local
Dim tmpDate As DateTime = New DateTime(Now.Ticks, DateTimeKind.Utc)
Dim res as String = tmpDate.toString("o") '2009-06-15T13:45:30.0000000Z
DateTimeKind.Utc
2009-06-15T13:45:30.0000000-07:00
DateTimeKind.未指定
2009-06-15T13:45:30.0000000Z
.NET为我们提供了具有以下选项的枚举:
2009-06-15T13:45:30.0000000
注意:如果将VisualStudio2008“watch utility”应用于toString(“o”)部分,可能会得到不同的结果,我不知道这是否是错误,但在这种情况下,如果正在调试,则使用字符串变量会获得更好的结果
来源:(MSDN)这些答案中的大多数都有毫秒/微秒,这显然不受ISO8601支持。正确答案是:
'2009-06-15T13:45:30.0000000-07:00
Dim strTmp1 As String = New DateTime(Now.Ticks, DateTimeKind.Local).ToString("o")
'2009-06-15T13:45:30.0000000Z
Dim strTmp2 As String = New DateTime(Now.Ticks, DateTimeKind.Utc).ToString("o")
'2009-06-15T13:45:30.0000000
Dim strTmp3 As String = New DateTime(Now.Ticks, DateTimeKind.Unspecified).ToString("o")
参考资料:
您有几个选项,包括“往返(“O”)格式说明符”
输出
var date1 = new DateTime(2008, 3, 1, 7, 0, 0);
Console.WriteLine(date1.ToString("O"));
Console.WriteLine(date1.ToString("s", System.Globalization.CultureInfo.InvariantCulture));
但是,DateTime+时区可能会出现博客文章中描述的其他问题:
DateTime中有无数陷阱,这些陷阱旨在给您的代码带来错误:
1.-带有DateTimeKind.Unspecified的DateTime值是坏消息
2.-DateTime在进行比较时不关心UTC/Local
3.-DateTime值不知道标准格式字符串
4.-解析带有日期时间的UTC标记的字符串不能保证UTC时间
有趣的是,自定义格式“yyyy-MM-ddTHH:MM:ssK”(不带ms)是最快的格式方法
同样有趣的是,“S”格式在经典上速度慢,在核心上速度快
当然,数字非常接近,某些行之间的差异不显著(带有后缀\u验证的测试与没有后缀的测试相同,证明结果的可重复性)
代码:
公共类基准DateTimeFormat
{
public static DateTime DateTime=DateTime.Now;
[基准]
公共字符串CustomDev1()
{
var d=dateTime.ToUniversalTime();
var sb=新的StringBuilder(20);
sb.追加(d.年)。追加(“-”;
如果(d.Month格式类似于2018-06-22T13:04:16,可以在API使用的URI中传递:
public class BenchmarkDateTimeFormat
{
public static DateTime dateTime = DateTime.Now;
[Benchmark]
public string CustomDev1()
{
var d = dateTime.ToUniversalTime();
var sb = new StringBuilder(20);
sb.Append(d.Year).Append("-");
if (d.Month <= 9)
sb.Append("0");
sb.Append(d.Month).Append("-");
if (d.Day <= 9)
sb.Append("0");
sb.Append(d.Day).Append("T");
if (d.Hour <= 9)
sb.Append("0");
sb.Append(d.Hour).Append(":");
if (d.Minute <= 9)
sb.Append("0");
sb.Append(d.Minute).Append(":");
if (d.Second <= 9)
sb.Append("0");
sb.Append(d.Second).Append("Z");
var text = sb.ToString();
return text;
}
[Benchmark]
public string CustomDev2()
{
var u = dateTime.ToUniversalTime();
var sb = new StringBuilder(20);
var y = u.Year;
var d = u.Day;
var M = u.Month;
var h = u.Hour;
var m = u.Minute;
var s = u.Second;
sb.Append(y).Append("-");
if (M <= 9)
sb.Append("0");
sb.Append(M).Append("-");
if (d <= 9)
sb.Append("0");
sb.Append(d).Append("T");
if (h <= 9)
sb.Append("0");
sb.Append(h).Append(":");
if (m <= 9)
sb.Append("0");
sb.Append(m).Append(":");
if (s <= 9)
sb.Append("0");
sb.Append(s).Append("Z");
var text = sb.ToString();
return text;
}
[Benchmark]
public string CustomDev2WithMS()
{
var u = dateTime.ToUniversalTime();
var sb = new StringBuilder(23);
var y = u.Year;
var d = u.Day;
var M = u.Month;
var h = u.Hour;
var m = u.Minute;
var s = u.Second;
var ms = u.Millisecond;
sb.Append(y).Append("-");
if (M <= 9)
sb.Append("0");
sb.Append(M).Append("-");
if (d <= 9)
sb.Append("0");
sb.Append(d).Append("T");
if (h <= 9)
sb.Append("0");
sb.Append(h).Append(":");
if (m <= 9)
sb.Append("0");
sb.Append(m).Append(":");
if (s <= 9)
sb.Append("0");
sb.Append(s).Append(".");
sb.Append(ms).Append("Z");
var text = sb.ToString();
return text;
}
[Benchmark]
public string FormatO()
{
var text = dateTime.ToUniversalTime().ToString("o");
return text;
}
[Benchmark]
public string FormatS()
{
var text = string.Concat(dateTime.ToUniversalTime().ToString("s"),"Z");
return text;
}
[Benchmark]
public string FormatS_Verify()
{
var text = string.Concat(dateTime.ToUniversalTime().ToString("s"), "Z");
return text;
}
[Benchmark]
public string CustomFormatK()
{
var text = dateTime.ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ssK");
return text;
}
[Benchmark]
public string CustomFormatK_Verify()
{
var text = dateTime.ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ssK");
return text;
}
}
注意:根据您在终端上进行的转换,您将使用第一行(最像它)或第二行
确保仅在本地时间应用格式,因为“zzz”是UTC转换的时区信息
令人惊讶的是,没有人提出:
System.DateTime.UtcNow.ToString(“u”).Replace(“”,'T’)
#使用PowerShell核心进行演示
#小写“u”格式
[系统日期时间]::UtcNow.ToString(“u”)
>2020-02-06 01:00:32Z
#带替换的小写“u”格式
[系统日期时间]::UtcNow.ToString(“u”).替换(“”,'T')
>2020-02-06T01:00:32Z
它几乎能让你一路得到你想要的东西(这更像是一种表现)
增加:
我决定使用答案中的基准来比较它的性能
tl:dr;虽然价格昂贵,但在我那台破旧的笔记本电脑上仍然只有半毫秒多一点:-)
实施:
[基准测试]
公共字符串ReplaceU()
{
var text=dateTime.ToUniversalTime().ToString(“u”).Replace(“”,'T');
返回文本;
}
结果:
DateTime.Now.ToString("yyyy-MM-dd'T'HH:mm:ss zzz");
DateTime.Now.ToString("O");
使用Newtonsoft.Json,您可以
// * Summary *
BenchmarkDotNet=v0.11.5, OS=Windows 10.0.19002
Intel Xeon CPU E3-1245 v3 3.40GHz, 1 CPU, 8 logical and 4 physical cores
.NET Core SDK=3.0.100
[Host] : .NET Core 3.0.0 (CoreCLR 4.700.19.46205, CoreFX 4.700.19.46214), 64bit RyuJIT
DefaultJob : .NET Core 3.0.0 (CoreCLR 4.700.19.46205, CoreFX 4.700.19.46214), 64bit RyuJIT
| Method | Mean | Error | StdDev |
|--------------------- |---------:|----------:|----------:|
| CustomDev1 | 562.4 ns | 11.135 ns | 10.936 ns |
| CustomDev2 | 525.3 ns | 3.322 ns | 3.107 ns |
| CustomDev2WithMS | 609.9 ns | 9.427 ns | 8.356 ns |
| FormatO | 356.6 ns | 6.008 ns | 5.620 ns |
| FormatS | 589.3 ns | 7.012 ns | 6.216 ns |
| FormatS_Verify | 599.8 ns | 12.054 ns | 11.275 ns |
| CustomFormatK | 549.3 ns | 4.911 ns | 4.594 ns |
| CustomFormatK_Verify | 539.9 ns | 2.917 ns | 2.436 ns |
| ReplaceU | 615.5 ns | 12.313 ns | 11.517 ns |
// * Hints *
Outliers
BenchmarkDateTimeFormat.CustomDev2WithMS: Default -> 1 outlier was removed (668.16 ns)
BenchmarkDateTimeFormat.FormatS: Default -> 1 outlier was removed (621.28 ns)
BenchmarkDateTimeFormat.CustomFormatK: Default -> 1 outlier was detected (542.55 ns)
BenchmarkDateTimeFormat.CustomFormatK_Verify: Default -> 2 outliers were removed (557.07 ns, 560.95 ns)
// * Legends *
Mean : Arithmetic mean of all measurements
Error : Half of 99.9% confidence interval
StdDev : Standard deviation of all measurements
1 ns : 1 Nanosecond (0.000000001 sec)
// ***** BenchmarkRunner: End *****
示例:如其他答案中所述,DateTime
在设计上存在问题
点头时间
我建议使用来管理日期/时间值:
- 当地时间,,
2009-06-15T13:45:30.0000000
'2009-06-15T13:45:30.0000000-07:00
Dim strTmp1 As String = New DateTime(Now.Ticks, DateTimeKind.Local).ToString("o")
'2009-06-15T13:45:30.0000000Z
Dim strTmp2 As String = New DateTime(Now.Ticks, DateTimeKind.Utc).ToString("o")
'2009-06-15T13:45:30.0000000
Dim strTmp3 As String = New DateTime(Now.Ticks, DateTimeKind.Unspecified).ToString("o")
System.DateTime.Now.ToString("yyyy-MM-ddTHH:mm:ssK");
// or
System.DateTime.Now.ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ssK");
var date1 = new DateTime(2008, 3, 1, 7, 0, 0);
Console.WriteLine(date1.ToString("O"));
Console.WriteLine(date1.ToString("s", System.Globalization.CultureInfo.InvariantCulture));
2008-03-01T07:00:00.0000000
2008-03-01T07:00:00
BenchmarkDotNet=v0.10.5, OS=Windows 10.0.14393
Processor=Intel Core i5-2500K CPU 3.30GHz (Sandy Bridge), ProcessorCount=4
Frequency=3233539 Hz, Resolution=309.2587 ns, Timer=TSC
[Host] : Clr 4.0.30319.42000, 64bit RyuJIT-v4.6.1637.0
Clr : Clr 4.0.30319.42000, 64bit RyuJIT-v4.6.1637.0
Core : .NET Core 4.6.25009.03, 64bit RyuJIT
Method | Job | Runtime | Mean | Error | StdDev | Median | Min | Max | Rank | Gen 0 | Allocated |
--------------------- |----- |-------- |-----------:|----------:|----------:|-----------:|-----------:|-----------:|-----:|-------:|----------:|
CustomDev1 | Clr | Clr | 1,089.0 ns | 22.179 ns | 20.746 ns | 1,079.9 ns | 1,068.9 ns | 1,133.2 ns | 8 | 0.1086 | 424 B |
CustomDev2 | Clr | Clr | 1,032.3 ns | 19.897 ns | 21.289 ns | 1,024.7 ns | 1,000.3 ns | 1,072.0 ns | 7 | 0.1165 | 424 B |
CustomDev2WithMS | Clr | Clr | 1,168.2 ns | 16.543 ns | 15.474 ns | 1,168.5 ns | 1,149.3 ns | 1,189.2 ns | 10 | 0.1625 | 592 B |
FormatO | Clr | Clr | 1,563.7 ns | 31.244 ns | 54.721 ns | 1,532.5 ns | 1,497.8 ns | 1,703.5 ns | 14 | 0.2897 | 976 B |
FormatS | Clr | Clr | 1,243.5 ns | 24.615 ns | 31.130 ns | 1,229.3 ns | 1,200.6 ns | 1,324.2 ns | 13 | 0.2865 | 984 B |
FormatS_Verify | Clr | Clr | 1,217.6 ns | 11.486 ns | 10.744 ns | 1,216.2 ns | 1,205.5 ns | 1,244.3 ns | 12 | 0.2885 | 984 B |
CustomFormatK | Clr | Clr | 912.2 ns | 17.915 ns | 18.398 ns | 916.6 ns | 878.3 ns | 934.1 ns | 4 | 0.0629 | 240 B |
CustomFormatK_Verify | Clr | Clr | 894.0 ns | 3.877 ns | 3.626 ns | 893.8 ns | 885.1 ns | 900.0 ns | 3 | 0.0636 | 240 B |
CustomDev1 | Core | Core | 989.1 ns | 12.550 ns | 11.739 ns | 983.8 ns | 976.8 ns | 1,015.5 ns | 6 | 0.1101 | 423 B |
CustomDev2 | Core | Core | 964.3 ns | 18.826 ns | 23.809 ns | 954.1 ns | 935.5 ns | 1,015.6 ns | 5 | 0.1267 | 423 B |
CustomDev2WithMS | Core | Core | 1,136.0 ns | 21.914 ns | 27.714 ns | 1,138.1 ns | 1,099.9 ns | 1,200.2 ns | 9 | 0.1752 | 590 B |
FormatO | Core | Core | 1,201.5 ns | 16.262 ns | 15.211 ns | 1,202.3 ns | 1,178.2 ns | 1,225.5 ns | 11 | 0.0656 | 271 B |
FormatS | Core | Core | 993.5 ns | 19.272 ns | 24.372 ns | 999.4 ns | 954.2 ns | 1,029.5 ns | 6 | 0.0633 | 279 B |
FormatS_Verify | Core | Core | 1,003.1 ns | 17.577 ns | 16.442 ns | 1,009.2 ns | 976.1 ns | 1,024.3 ns | 6 | 0.0674 | 279 B |
CustomFormatK | Core | Core | 878.2 ns | 17.017 ns | 20.898 ns | 877.7 ns | 851.4 ns | 928.1 ns | 2 | 0.0555 | 215 B |
CustomFormatK_Verify | Core | Core | 863.6 ns | 3.968 ns | 3.712 ns | 863.0 ns | 858.6 ns | 870.8 ns | 1 | 0.0550 | 215 B |
public class BenchmarkDateTimeFormat
{
public static DateTime dateTime = DateTime.Now;
[Benchmark]
public string CustomDev1()
{
var d = dateTime.ToUniversalTime();
var sb = new StringBuilder(20);
sb.Append(d.Year).Append("-");
if (d.Month <= 9)
sb.Append("0");
sb.Append(d.Month).Append("-");
if (d.Day <= 9)
sb.Append("0");
sb.Append(d.Day).Append("T");
if (d.Hour <= 9)
sb.Append("0");
sb.Append(d.Hour).Append(":");
if (d.Minute <= 9)
sb.Append("0");
sb.Append(d.Minute).Append(":");
if (d.Second <= 9)
sb.Append("0");
sb.Append(d.Second).Append("Z");
var text = sb.ToString();
return text;
}
[Benchmark]
public string CustomDev2()
{
var u = dateTime.ToUniversalTime();
var sb = new StringBuilder(20);
var y = u.Year;
var d = u.Day;
var M = u.Month;
var h = u.Hour;
var m = u.Minute;
var s = u.Second;
sb.Append(y).Append("-");
if (M <= 9)
sb.Append("0");
sb.Append(M).Append("-");
if (d <= 9)
sb.Append("0");
sb.Append(d).Append("T");
if (h <= 9)
sb.Append("0");
sb.Append(h).Append(":");
if (m <= 9)
sb.Append("0");
sb.Append(m).Append(":");
if (s <= 9)
sb.Append("0");
sb.Append(s).Append("Z");
var text = sb.ToString();
return text;
}
[Benchmark]
public string CustomDev2WithMS()
{
var u = dateTime.ToUniversalTime();
var sb = new StringBuilder(23);
var y = u.Year;
var d = u.Day;
var M = u.Month;
var h = u.Hour;
var m = u.Minute;
var s = u.Second;
var ms = u.Millisecond;
sb.Append(y).Append("-");
if (M <= 9)
sb.Append("0");
sb.Append(M).Append("-");
if (d <= 9)
sb.Append("0");
sb.Append(d).Append("T");
if (h <= 9)
sb.Append("0");
sb.Append(h).Append(":");
if (m <= 9)
sb.Append("0");
sb.Append(m).Append(":");
if (s <= 9)
sb.Append("0");
sb.Append(s).Append(".");
sb.Append(ms).Append("Z");
var text = sb.ToString();
return text;
}
[Benchmark]
public string FormatO()
{
var text = dateTime.ToUniversalTime().ToString("o");
return text;
}
[Benchmark]
public string FormatS()
{
var text = string.Concat(dateTime.ToUniversalTime().ToString("s"),"Z");
return text;
}
[Benchmark]
public string FormatS_Verify()
{
var text = string.Concat(dateTime.ToUniversalTime().ToString("s"), "Z");
return text;
}
[Benchmark]
public string CustomFormatK()
{
var text = dateTime.ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ssK");
return text;
}
[Benchmark]
public string CustomFormatK_Verify()
{
var text = dateTime.ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ssK");
return text;
}
}
public static string FormatDateTime(DateTime dateTime)
{
return dateTime.ToString("s", System.Globalization.CultureInfo.InvariantCulture);
}
DateTime.Now.ToString("yyyy-MM-dd'T'HH:mm:ss zzz");
DateTime.Now.ToString("O");
// * Summary *
BenchmarkDotNet=v0.11.5, OS=Windows 10.0.19002
Intel Xeon CPU E3-1245 v3 3.40GHz, 1 CPU, 8 logical and 4 physical cores
.NET Core SDK=3.0.100
[Host] : .NET Core 3.0.0 (CoreCLR 4.700.19.46205, CoreFX 4.700.19.46214), 64bit RyuJIT
DefaultJob : .NET Core 3.0.0 (CoreCLR 4.700.19.46205, CoreFX 4.700.19.46214), 64bit RyuJIT
| Method | Mean | Error | StdDev |
|--------------------- |---------:|----------:|----------:|
| CustomDev1 | 562.4 ns | 11.135 ns | 10.936 ns |
| CustomDev2 | 525.3 ns | 3.322 ns | 3.107 ns |
| CustomDev2WithMS | 609.9 ns | 9.427 ns | 8.356 ns |
| FormatO | 356.6 ns | 6.008 ns | 5.620 ns |
| FormatS | 589.3 ns | 7.012 ns | 6.216 ns |
| FormatS_Verify | 599.8 ns | 12.054 ns | 11.275 ns |
| CustomFormatK | 549.3 ns | 4.911 ns | 4.594 ns |
| CustomFormatK_Verify | 539.9 ns | 2.917 ns | 2.436 ns |
| ReplaceU | 615.5 ns | 12.313 ns | 11.517 ns |
// * Hints *
Outliers
BenchmarkDateTimeFormat.CustomDev2WithMS: Default -> 1 outlier was removed (668.16 ns)
BenchmarkDateTimeFormat.FormatS: Default -> 1 outlier was removed (621.28 ns)
BenchmarkDateTimeFormat.CustomFormatK: Default -> 1 outlier was detected (542.55 ns)
BenchmarkDateTimeFormat.CustomFormatK_Verify: Default -> 2 outliers were removed (557.07 ns, 560.95 ns)
// * Legends *
Mean : Arithmetic mean of all measurements
Error : Half of 99.9% confidence interval
StdDev : Standard deviation of all measurements
1 ns : 1 Nanosecond (0.000000001 sec)
// ***** BenchmarkRunner: End *****
JsonConvert.SerializeObject(DateTime.UtcNow)
var instant1 = Instant.FromUtc(2020, 06, 29, 10, 15, 22);
var utcZonedDateTime = new ZonedDateTime(instant1, DateTimeZone.Utc);
utcZonedDateTime.ToString("yyyy-MM-ddTHH:mm:ss'Z'", CultureInfo.InvariantCulture);
// 2020-06-29T10:15:22Z
var instant2 = Instant.FromDateTimeUtc(new DateTime(2020, 06, 29, 10, 15, 22, DateTimeKind.Utc));
var amsterdamZonedDateTime = new ZonedDateTime(instant2, DateTimeZoneProviders.Tzdb["Europe/Amsterdam"]);
amsterdamZonedDateTime.ToString("yyyy-MM-ddTHH:mm:ss'Z'", CultureInfo.InvariantCulture);
// 2020-06-29T12:15:22Z
services
.AddMvc()
.AddJsonOptions(options =>
{
var settings=options.SerializerSettings;
settings.DateParseHandling = DateParseHandling.None;
settings.ConfigureForNodaTime(DateTimeZoneProviders.Tzdb);
});