Can't convert time to ISO 8601 using C#

Question

Consider this code:

TimeStamp.Text = BlogComment.Date.UtcNow.ToString("yyyy-MM-ddTHH\:mm\:ss.fffffffzzz");

BlogComment.Date is a DateTime object with its date set. TimeStamp is just a literal.

I keep getting unrecognised escape sequence. How can I fix this problem?

BrokenGlass · Accepted Answer · 2011-03-07T01:43:37.913

3

You want a string literal - prefixing a string with @ will not parse the string for escape sequences like you have in your string but take it in "literal" form.

@"yyyy-MM-ddTHH\:mm\:ss.fffffffzzz"

Edit:

Also there is no UtNow property on DateTime - this is a static property only available on the DateTime class. You can just write:

TimeStamp.Text = BlogComment.Date.ToString(@"yyyy-MM-ddTHH\:mm\:ss.fffffffzzz");

or if your intention was to convert the time to UTC:

TimeStamp.Text = BlogComment.Date
                            .ToUniversalTime()
                            .ToString(@"yyyy-MM-ddTHH\:mm\:ss.fffffffzzz");

edited Mar 07 '11 at 01:43

answered Mar 07 '11 at 01:37

BrokenGlass

158,293
28
286
335

Thanks for answer but I get 'Member 'System.DateTime.UtcNow.get' cannot be accessed with an instance reference; qualify it with a type name instead' – Tom Gullen Mar 07 '11 at 01:38
That's because UtcNow is a static property. Perhaps you meant ...Date.ToUniversalTime()...? – Peter Huene Mar 07 '11 at 01:39
@Peter, thanks, how do I resolve that then? I'm confused now. All I'm trying to do is display it in this format for a Jquery plugin – Tom Gullen Mar 07 '11 at 01:41
var text = DateTime.UtcNow.ToString(@"yyyy-MM-ddTHH\:mm\:ss.fffffffzzz"); Prefix the method with the type name. – Ritch Melton Mar 07 '11 at 01:42
@Ritch, thanks, but thats only for now, I need it for any given datetime that is in the past – Tom Gullen Mar 07 '11 at 01:43
Excellent, thank you! I'll read up more on this so I understand it fully. – Tom Gullen Mar 07 '11 at 01:47
2

@Tom: On a side note, if these dates are stored in a database, I'd recommend storing them in UTC and converting to local as needed. – Peter Huene Mar 07 '11 at 01:50
Good luck. I'm glad you got the answer you were looking for. – Ritch Melton Mar 07 '11 at 01:51

Bala R · Answer 2 · 2011-03-07T01:43:35.693

2

EDIT:

 TimeStamp.Text =  BlogComment.Date.ToUniversalTime().ToString(@"yyyy-MM-ddTHH\:mm\:ss.fffffffzzz");

edited Mar 07 '11 at 01:43

answered Mar 07 '11 at 01:36

Bala R

107,317
23
199
210

Thanks for the answer but I get a red squiggle, UTC.get cannot be accessed with instance reference. – Tom Gullen Mar 07 '11 at 01:37
Thanks! +1 for you, I appreciate your help. – Tom Gullen Mar 07 '11 at 01:47

score 1 · Answer 3 · edited Jun 18 '15 at 14:04

1

Try this:

Stamp.Text = BlogComment.Date.ToString("yyyy-MM-ddTHH\\:mm\\:ss.fffffffzzz");

Or

Stamp.Text = BlogComment.Date.ToString(@"yyyy-MM-ddTHH:mm:ss.fffffffzzz");

My mistake: The \ is indeed required, because it might be a custom format specifier.

And if you just want the current time, use

Stamp.Text = DateTime.UtcNow.ToString(@"yyyy-MM-ddTHH\:mm\:ss.fffffffzzz");

UtcNow is static. It should not be accessed from an instance. It should be accessed from the class itself.

Alternatively, you might want:

Stamp.Text = BlogComment.Date.ToUniversalTime().ToString(@"yyyy-MM-ddTHH\:mm\:ss.fffffffzzz");

This would get you the universal time of the Date in BlogComment.

edited Jun 18 '15 at 14:04

Peter Mortensen

30,738
21
105
131

answered Mar 07 '11 at 01:46

Fun Mun Pieng

6,751
3
28
30

1

There is one important reason. The `:` is understood to be the (invariant) time separator in a DateTime format string. When not escaped, the `:` may be transformed to the target cultures `DateTimeFormat.TimeSeparator`. Try your output by specifying the culture as Italian (`it-IT`) and you will see that that time is `2011-03-07T02.03.58.2693372+13:00` – Robert Paulson Mar 07 '11 at 02:07
Instead of escaping, it would be better to use the invariant format provider `DateTime.UtcNow.ToString("yyyy-MM-ddTHH:mm:ss.fffffffzzz", DateTimeFormatInfo.InvariantInfo)` – Robert Paulson Mar 07 '11 at 02:57
Sorry I need to correct myself. For .net DateTime formatting, `/` is the invariant date separator, and `:` is the invariant time separator. – Robert Paulson Mar 07 '11 at 03:19

score 0 · Answer 4 · answered Apr 16 '14 at 02:21

DateTime.UtcNow..ToString("o");

(o) Roundtrip (local):. . . . 2006-04-17T14:22:48.2698750-07:00

(o) Roundtrip (UTC):. . . . . 2006-04-17T21:22:48.2698750Z

(o) Roundtrip (Unspecified):. 2000-03-20T13:02:03.0000000

http://msdn.microsoft.com/en-us/library/zdtaw1bw(v=vs.85).aspx

score 0 · Answer 5 · edited May 23 '17 at 11:51

When dealing with escaping characters in a DateTime format string, there's a similar question where @Oppositional's writes

When using custom format strings with a DateTime, it is important to remeber that you need to escape your seperators using single quotes.

string time = DateTime.UtcNow.ToString(
    "yyyy'-'MM'-'dd'T'HH':'mm':'ss'.'fffffffzzz",
    DateTimeFormatInfo.InvariantInfo);

The characters surrounded by the single quotes ' are literal strings inside a DateTime format string.

However, escaping the - and : is redundant if you are also specifying the Invariant culture. You should always specify the culture when formatting dates and times.

It's also important to note that / and : are the (invariant) date and time separators in a DateTime format string. DateTime.ToString will use the current cultures to transform them as necessary. For example, Italian (it-IT) has the . as its time separator. Similarly fr-CH has a date separator of .

You can see this escaping in action if you take a look at System.Globalization.CultureInfo.InvariantCulture.DateTimeFormat.UniversalSortableDateTimePattern which is yyyy'-'MM'-'dd HH':'mm':'ss'Z'

Can't convert time to ISO 8601 using C#

5 Answers5