Date format for conversion in c#

Question

is there anyone there who can tell me what type of a date format is this '1110620'? And how can I convert this to a 'yyyy-MM-dd' format. Any help is highly appreciated. Thanks!

It would help immensely if you already had some examples on both sides - for instance, did you obtain this `1110620` value today, and is it meant to represent today's date? — Damien_The_Unbeliever, Nov 29 '11 at 08:15
Reliably determining the format of data based on one sample and no further information is generally not possible, and basically the same problem as [detecting the encoding of a text(file)](http://stackoverflow.com/a/90956/21567). — Christian.K, Nov 29 '11 at 08:22
Does anyone know what today is in Captain Kirks "stardate"? Rounding allowed. — H H, Nov 29 '11 at 08:26
@HenkHolterman: That would be [64374.2](http://trekguide.com/Stardates.htm). But only for Kirk's timeline. They have to be calculated differently for the NG stuff. Anyway it looks like "startdate" also includes time. ;-) — Christian.K, Nov 29 '11 at 08:29
Can you post an example where you know both the number and the date it represents? — CodesInChaos, Nov 29 '11 at 19:02

score 2 · Answer 1 · answered Nov 29 '11 at 08:22

2

DateTime d;
if (DateTime.TryParse("1110620", CultureInfo.InvariantCulture, DateTimeStyles.None, out d))
    string r = d.ToString("yyyy-MM-dd");
else
    throw new Exception();

answered Nov 29 '11 at 08:22

abatishchev

98,240
88
296
433

Good solution, checking for possible errors. Upvoted! :) – Marco Nov 29 '11 at 08:27
But why the assumption of InvariantCulture? You should loop through all cultures. – H H Nov 29 '11 at 08:36
@Henk: What for? I'm sure there is no culture that will be able to parse it if invariant will be not. – abatishchev Nov 29 '11 at 09:03

score 1 · Answer 2 · answered Nov 29 '11 at 08:18

1

This should work:

string dt = "1110620";
DateTime dt = DateTime.ParseExact(dt, "yyyMMdd", 
                                  CultureInfo.CultureInvariant);

or you can try (not elegant but works)

        int start = dt.Length - 4;
        DateTime d = new DateTime(
            int.Parse(dt.Substring(0, start)),
            int.Parse(dt.Substring(start, 2)),
            int.Parse(dt.Substring(2 + start, 2)));

answered Nov 29 '11 at 08:18

Marco

56,740
14
129
152

@Henk: Have you any other, non-joke ideas what format is represented? – abatishchev Nov 29 '11 at 08:25
@HenkHolterman: I thought OP was wrong with date... but he confirmed it was correct. I don't know if my answer is what OP is searching for... really, don't know. :) – Marco Nov 29 '11 at 08:26
@abatishchev : if it's a Julian daynumber it means 17 Sep 1673. – H H Nov 29 '11 at 08:31

score 0 · Answer 3 · answered Nov 29 '11 at 08:17

0

The above format seems to be - yyyMMdd. You can write c# method to convert it accordingly. Refer MSDN for more details.

answered Nov 29 '11 at 08:17

Nitin Rastogi

1,446
16
30

CodesInChaos · Answer 4 · 2011-11-29T12:38:13.833

My guess is that the first 3 digits are an extension of a two digit year. Where 100 corresponds to the year 2000.

So the format was originally yyMMdd and or perhaps (year-1900)*10000+month*100+day which extends logically to years after 2000 by prefixing a 1. This also preserves integer sorting order.

So to parse it you could:

day=input%100;
month=input/100%100;
year=input/10000+1900;

With this formula 1110620 corresponds to 2011-06-20

But unless you explain what your example should mean, this is just speculation.

My first guess was that it might be days since a certain date, but this would put the origin at around 1000BC, which is unlikely.

Date format for conversion in c#

4 Answers4