获取日期为DateTime对象，而不是字符串。然后你可以按照你想要的格式格式化它。

MM/dd/yyyy 08/22/2006 dddd, dd MMMM yyyy Tuesday, 22 August 2006 dddd, dd MMMM yyyy HH:mm Tuesday, 22 August 2006 06:30 dddd, dd MMMM yyyy hh:mm tt Tuesday, 22 August 2006 06:30 AM dddd, dd MMMM yyyy H:mm Tuesday, 22 August 2006 6:30 dddd, dd MMMM yyyy h:mm tt Tuesday, 22 August 2006 6:30 AM dddd, dd MMMM yyyy HH:mm:ss Tuesday, 22 August 2006 06:30:07 MM/dd/yyyy HH:mm 08/22/2006 06:30 MM/dd/yyyy hh:mm tt 08/22/2006 06:30 AM MM/dd/yyyy H:mm 08/22/2006 6:30 MM/dd/yyyy h:mm tt 08/22/2006 6:30 AM MM/dd/yyyy HH:mm:ss 08/22/2006 06:30:07

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实际上，您已经自己编写了格式。

你的日期。ToString（“yyyyMMddHHmmss”）

MM =两位数月 Mm =两位数的分钟 HH =两位数小时，24小时钟 Hh =两位数小时，12小时钟

其他一切都应该不言自明。

DateTime.Now.ToString("yyyyMMddHHmmss"); // case sensitive

使用c# 6.0

$"Date-{DateTime.Now:yyyyMMddHHmmss}"

指定格式化的DateTime为Utc:

步骤1 -初始日期

var initialDtm = DateTime.Now;

步骤2 -格式日期为愿意("yyyyMMddHHmmss")

var formattedDtm = DateTime.ParseExact(initialDtm.ToString("yyyyMMddHHmmss"), "yyyyMMddHHmmss", CultureInfo.InvariantCulture);    

步骤3 -指定日期类型(Utc)

var specifiedDtm = DateTime.SpecifyKind(formattedDtm, DateTimeKind.Utc);

DateTime.Now.ToString("MM/dd/yyyy") 05/29/2015
DateTime.Now.ToString("dddd, dd MMMM yyyy") Friday, 29 May 2015
DateTime.Now.ToString("dddd, dd MMMM yyyy") Friday, 29 May 2015 05:50
DateTime.Now.ToString("dddd, dd MMMM yyyy") Friday, 29 May 2015 05:50 AM
DateTime.Now.ToString("dddd, dd MMMM yyyy") Friday, 29 May 2015 5:50
DateTime.Now.ToString("dddd, dd MMMM yyyy") Friday, 29 May 2015 5:50 AM
DateTime.Now.ToString("dddd, dd MMMM yyyy HH:mm:ss")    Friday, 29 May 2015 05:50:06
DateTime.Now.ToString("MM/dd/yyyy HH:mm")   05/29/2015 05:50
DateTime.Now.ToString("MM/dd/yyyy hh:mm tt")    05/29/2015 05:50 AM
DateTime.Now.ToString("MM/dd/yyyy H:mm")    05/29/2015 5:50
DateTime.Now.ToString("MM/dd/yyyy h:mm tt") 05/29/2015 5:50 AM
DateTime.Now.ToString("MM/dd/yyyy HH:mm:ss")    05/29/2015 05:50:06
DateTime.Now.ToString("MMMM dd")    May 29
DateTime.Now.ToString("yyyy’-‘MM’-‘dd’T’HH’:’mm’:’ss.fffffffK") 2015-05-16T05:50:06.7199222-04:00
DateTime.Now.ToString("ddd, dd MMM yyy HH’:’mm’:’ss ‘GMT’") Fri, 16 May 2015 05:50:06 GMT
DateTime.Now.ToString("yyyy’-‘MM’-‘dd’T’HH’:’mm’:’ss")  2015-05-16T05:50:06
DateTime.Now.ToString("HH:mm")  05:50
DateTime.Now.ToString("hh:mm tt")   05:50 AM
DateTime.Now.ToString("H:mm")   5:50
DateTime.Now.ToString("h:mm tt")    5:50 AM
DateTime.Now.ToString("HH:mm:ss")   05:50:06
DateTime.Now.ToString("yyyy MMMM")  2015 May