How do I convert to DateTime when the time is a decimal?

Question

I have a data table, from Sage 100 ERP to be specific, that uses two separate columns to store the updated date and time (DateUpdated and TimeUpdated). I need to convert the data in these two fields to a DateTime object for comparisons. The dates look like "mm/dd/yyyy 12:00 AM" and the time is a decimal like 14.29297. So far I have been able to convert the time to the minute as follows:

private DateTime GetDateTime(string date, decimal time)
    {
        int hour = int.Parse(Math.Floor(time).ToString());
        decimal minTemp = decimal.Parse((60 * (time - hour)).ToString());
        int min = int.Parse(Math.Round(minTemp).ToString());
        int sec = int.Parse(Math.Round(60 * (minTemp - min)).ToString());

        string datetime = date + " " + hour.ToString() + ":" + min.ToString();

        return DateTime.Parse(datetime);
    }

I remove the 12:00AM from the date string before I pass it to this method. This works, but I'm loosing the seconds which is very important.

How can I convert the time to hours, minutes, and seconds?

Might want to refer to the following post: http://stackoverflow.com/questions/1933320/convert-a-date-to-string-in-javascript — Sparebrain, Dec 20 '13 at 18:31
I also see that you have not appended sec to datetime string. — hanskishore, Dec 20 '13 at 18:38
The decimal is the hours, so for example, 2.5 would be 2:30. — Evil August, Dec 20 '13 at 19:58

score 1 · Answer 1 · answered Dec 21 '13 at 04:29

1

Just parse what you have:

private DateTime GetDateTime(string date, decimal time)
{
    DateTime dt = DateTime.ParseExact(date, "MM/dd/yyyy hh:mm tt",
                                      CultureInfo.InvariantCulutre);

    double hours = Convert.ToDouble(time);

    return dt.AddHours(hours);
}

Of course, it would be a lot easier if you had the correct data types to begin with. I have a feeling somewhere you have a DateTime and a double anyway (perhaps when you read the data from the database), and you are improperly converting them to string and decimal.

answered Dec 21 '13 at 04:29

Matt Johnson-Pint

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Also, I was getting an exception with ParseExact, so I am just doing DateTime.Parse(date). It is giving me the correct DateTime values. – Evil August Dec 23 '13 at 14:42
1

If you were getting an exception, then you probably have data that doesn't match the format supplied. Now you are probably hiding the problem. Be careful. – Matt Johnson-Pint Dec 23 '13 at 17:33

score 1 · Accepted Answer · answered Dec 21 '13 at 04:43

1

It looks like you could avoid all that extra processing and just do this:

DateTime GetDateTime(string date, decimal time)
{
    return DateTime.Parse(datetime).AddHours((double)time);
}

answered Dec 21 '13 at 04:43

Cory Nelson

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Thanks Cory, this is what I ended up doing based on Matt's answer. – Evil August Dec 23 '13 at 15:36

score 0 · Answer 3 · answered Dec 20 '13 at 18:35

0

if it's not a typo - you are missing to append seconds value to the datetime string.

Replace This:

string datetime = date + " " + hour.ToString() + ":" + min.ToString();

With this:

string datetime = date + " " + hour.ToString() + ":" + min.ToString()+ ":" + sec.ToString();

answered Dec 20 '13 at 18:35

Sudhakar Tillapudi

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I don't believe the seconds calculation is correct. It always comes out to -1. – Evil August Dec 20 '13 at 18:39
@user2842689: could you please provide us the sample decimal time value? – Sudhakar Tillapudi Dec 20 '13 at 18:39
The time is like 14.29297 – Evil August Dec 20 '13 at 18:52

score 0 · Answer 4 · answered Dec 20 '13 at 18:35

0

Assuming your calculations are correct, did you try appending the second component to the datetime variable as follows:

string datetime = date + " " + hour.ToString() + ":" + min.ToString() + ":" + sec.ToString()

answered Dec 20 '13 at 18:35

Klaus Nji

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score 0 · Answer 5 · answered Dec 20 '13 at 18:52

For the seconds try something like this:

int secTemp = int.Parse((Math.Round(60 * (minTemp - min))).ToString());
int sec = (secTemp<0?60 + secTemp:secTemp);
string datetime = date + " " + hour.ToString() + ":" + min.ToString()+ ":" + sec.ToString();

Hope it helps

score 0 · Answer 6 · answered Feb 24 '16 at 21:42

Covert Decimal to Hour and Minute for single Database field

        double convertData = 1.75
        TimeSpan timespan = TimeSpan.FromHours(convertData);
        string outputH = timespan.ToString("hh");
        string outputM = timespan.ToString("mm");

Output will be 1 hour / 45 min

How do I convert to DateTime when the time is a decimal?

6 Answers6