kinda got an issue that I cant solve right now.
I've got a discord bot running on my raspberry pi, which has a system for automated messages that are sent after a certain amount of time, or an exact date, has passed.
My code works on Windows when debugging there, but the console throws a warning on Linux when running the published project.
The date is taken from a table in my MySQL database and put into a DataTable. The code that grabs the date from the DataRow is:
DateTime datetime = DateTime.ParseExact(row["datetime"].ToString(), "dd.MM.yyyy HH:mm:ss", CultureInfo.InvariantCulture);
Why is it happening? No matter how I format the string (dots, dashes or slashes), the warning persists. The messages are not sent.
I even tried removing invisible whitespaces with regex, doesnt work either.
(The regex in question, though I scrapped it since it yielded no fruit anyways)
Regex.Replace($"{row["datetime"].ToString()}", #"[^\d\s\.:]", string.Empty);
If RDBMS type is DateTime then why should we convert to string and then parse it back to DateTime? Let's do it direct:
DateTime datetime = Convert.ToDateTime(row["datetime"]);
and let .net convert boxed DateTime (row["datetime"] is of type object?) to DateTime
There are a couple issues--at the highest level, your ParseExact method is encountering a Date Time string that does not match the supplied format.
According to the code you posted, the expected format of is dd.MM.yyyy HH:mm:ss, and in your exception exception, shows a Date time string (8/2/2021 2:00:00 PM) that does not match:
contains / and your expected format has .
dd is a 2-digit day, but the input date time string only has single digit days
MM expects a two digit month and the input date time only has a single digit month
the string contains AM/PM, and your format neglects to account for that.
Finally it's not clear if your date format is Month Day Year, or Day Month year.
The second issue, is that ParseExact should be enclosed in a try/catch block, so that your code can handle the case when an unexpected formatted date time string is passed in, and not crash.
To solve this, wrap your call into a try/catch, and gracefully handle the FormatException
And then make sure the Format string matches the expected input string.
Here is the .NET reference for the various DateTime format tokens
The error message is letting you know the issue.
You have :
DateTime datetime = DateTime.ParseExact(row["datetime"].ToString(), "dd.MM.yyyy HH:mm:ss", CultureInfo.InvariantCulture);
Notable, you are saying that the date format is going to be "dd.MM.yyyy HH:mm:ss"
Then your error message is saying that you couldn't parse :
8/2/2021 2:00:00 PM
Which is essentially a format of "d/M/yyyy h:mm:ss tt" (Assuming that days come before months).
If you change your code to :
DateTime datetime = DateTime.ParseExact(row["datetime"].ToString(), "d/M/yyyy h:mm:ss tt", CultureInfo.InvariantCulture);
You should be good to go. DateTime.ParseExact does what it says on the tin, it parses the date format exactly how you say it should come. If you aren't sure you can use DateTime.Parse() (But you can occassionally run into issues where days/months are around the wrong way).
Tested using the following code :
var myDateString = "8/2/2021 2:00:00 PM";
DateTime datetime = DateTime.ParseExact(myDateString, "d/M/yyyy h:mm:ss tt", CultureInfo.InvariantCulture);
Console.WriteLine(datetime.ToString());
Related
I am writing a program to read log files, converting timestamps along the way. Currently, I am using DateTime.TryParseExact() to quickly analyze timestamps, ensuring things are correct. The issue I am running into is only AM designators are being recognized, PM are working without issue. I have isolated the issue in the below snippet:
string format = "M/dd/yyyy H:mm:ss tt";
string teststringPM = "1/21/2019 3:25:32 PM";
string teststringAM = "1/21/2019 3:25:32 AM";
DateTime placeholderPM;
DateTime placeholderAM;
DateTime.TryParseExact(teststringPM, format, System.Globalization.CultureInfo.InvariantCulture, System.Globalization.DateTimeStyles.None, out placeholderPM);
DateTime.TryParseExact(teststringAM, format, System.Globalization.CultureInfo.InvariantCulture, System.Globalization.DateTimeStyles.None, out placeholderAM);
Console.WriteLine("placeholderPM:");
Console.WriteLine(placeholderPM.ToString());
Console.WriteLine("placeholderAM:");
Console.WriteLine(placeholderAM.ToString());
The output from this looks like:
placeholderPM:
1/1/0001 12:00:00 AM
placeholderAM:
1/21/2019 3:25:32 AM
We can see that the placeholderPM is the default new datetime value. I have tried changing the IFormatProvider to en-US, without any change in behavior.
Any insight greatly appreciated!
It looks like you might be using the 'H' identifier instead of 'h'. This is an expected behavior as a upper case 'H' is used for 24 hour time. Using a lower case 'h' should resolve this issue.
For example, the format would become:
string format = "M/dd/yyyy h:mm:ss tt";
This goes into more detail
The following code will output 2018-10-03 16:40:50 (instead of 2018-03-10) :
DateTime dateTime = new DateTime();
DateTime.TryParse("10/03/2018 4:40:50 PM", out dateTime );
MessageBox.Show(dateTime.ToString());
The following code will parse the date correctly (2018-03-10)
dateTime = DateTime.ParseExact("10/03/2018 4:40:50 PM", "dd/MM/yyyy h:mm:ss tt", System.Globalization.CultureInfo.InvariantCulture);
MessageBox.Show(dateTime.ToString());
Is there any way to correctly parse this date without knowing the exact format?
The current culture of the server application is en-ca (English Canada) and I don't know the exact format of the string date to parse. at least is there a way to parse the date without the curious swap between the month and day? Sounds like an easy question but lost a lot of time reading and tried almost anything found here.
Thanks
End up using TryParseExact with an array list of known format. (ugly but it work)
There is no way to detect MM-DD-YYYY versus DD-MM-YYYY. Known limitation (this format is finally not supported by our application)
Thanks!
Before i begin to explain ,i need to tell I have tried all the possible solutions for this problem that are provided in stackoverflow. But doesn't work in windows 7.
On windows 7 parsing datetime is not working.
i have tried the following code snippets
DateTime.ParseExact(arr[TransactionDateIndex], "M/dd/yyyy h:mm:ss tt", null);
DateTime.ParseExact(arr[TransactionDateIndex], "M/d/yyyy h:mm:ss tt",CultureInfo.InvariantCulture);
DateTime.Parse(DateTime.Parse(arr[TransactionDateIndex]).ToString("M/d/yyyy h:mm:ss tt"),CultureInfo.InvariantCulture);
I have an input file which has a transaction date column and it can be in any valid Date-Time Format, right now in the file its (MM/dd/YYYY) which i need to convert to "M/d/yyyy h:mm:ss tt" format.
When running in XP this code works fine but in windows 7 even after trying ParseExact its showing the error.
Even if i use
if (DateTime.TryParse(input, out dateTime))
{
}
While running in windows 7,few records will be treated as invalid but same things will be parsed in XP.
If you r current datetime format is MM/dd/yyyy
then you should use as
string dateString = "02/15/2015"
DateTime dateValue = DateTime.ParseExact(dateString , "MM/dd/yyyy", CultureInfo.InvariantCulture);
And if you want to convert that to some other format like you mentioned M/d/yyyy h:mm:ss tt then you can add the .Tostring('M/d/yyyy h:mm:ss tt') to the date.
As read trough your question one more time you mentioned that it can be in any valid Date-Time Format if that is so and if your cultureInfo is fixed.
You can use something like the following, but be aware that more than one format might be able to parse the same date. For example 10/11/12 can be parsed as yyyy/MM/dd or MM/dd/yyyy, which are both valid US date formats. MM/dd/yyyy is more common, so it appears first in the list and is the one returned by the code below (if you use it with a US culture instead of the culture in the example).
string testValue = "02/15/2015";
DateTime result;
CultureInfo ci = CultureInfo.GetCultureInfo("sl-SI");
string[] fmts = ci.DateTimeFormat.GetAllDateTimePatterns();
Console.WriteLine(String.Join("\r\n", fmts));
if (DateTime.TryParseExact(testValue, fmts, ci, DateTimeStyles.AssumeLocal, out result)) {
Console.WriteLine(result.ToLongDateString());
}
And if the CultureInfo is also not fixed then you should fetch all the available countercultures and then get all formats from them and then parse the date time .
It may be the case that there is an invalid date in
arr[TransactionDateIndex]
So try with a hard-coded date first. then you could check all the values passed to date.parse using debug.write() (windows app) or trance.write() (asp.net) by using debug class in System.Diagnostics and check the output window for any inconsistent date format.
Finally you could place this code at the top of the method where this code appears:
System.Threading.Thread.CurrentCulture = CultureInfo.InvariantCulture;
How to populate C# DateTime object from this "03-06-2012 08:00 am" string.
I'm trying some code of follwoing type:
DateTime lectureTime = DateTime.Parse("03-06-2012 08:00 am");
I am using jQuery based this http://trentrichardson.com/examples/timepicker/ plugin to generate date time.
Update --
So many answers below and lot of stuff to clear basics for this small issue
From the below snapshot u can see what I tried and what i received during debugging in visual studio
string lectureTime = "03-06-2012 08:00 am";
DateTime time = DateTime.ParseExact(lectureTime , "dd-MM-yyyy hh:mm tt", CultureInfo.InvariantCulture);
dd: days [00-31]
MM: months [00-12]
yyyy: years [0000-9999]
'-': these are separated with a dash
hh: hours [00-12]
mm: minutes[00-60]
tt: time [am, pm] (case insensitive)
If you have the correct culture, your code works without modification. But you may be using a different date formatting from the program that generated the string.
I'd recommend always specifying a CultureInfo when:
Parsing a DateTime generated by another system.
Outputting a DateTime that will be parsed by another system (not just shown to your user).
Try this:
CultureInfo cultureInfo = new CultureInfo("en-GB"); // Or something else?
DateTime lectureTime = DateTime.Parse("03-06-2012 08:00 am", cultureInfo);
See it working online: ideone
Difference between DateTime.Parse and DateTime.ParseExact
If you want .NET to make its best effort at parsing the string then use DateTime.Parse. It can handle a wide variety of common formats.
If you know in advance exactly how the dates should be formatted, and you want to reject anything that differs from this format (even if it could be parsed correctly and without ambiguity) then use DateTime.ParseExact.
You need to use DateTime.ParseExact. Something like
DateTime lectureTime = DateTime.ParseExact("03-06-2012 08:00 am", "dd-MM-yyyy hh:mm tt", CultureInfo.InvariantCulture);
I am trying to parse a DateTime in C# and have the following lines of code:
string dt =Convert.ToString( DateTime.FromFileTime(e8.sts[counter8].TimeStamp));
string format = "dd-MM-yyyy HH:mm:ss";
DateTime dateTime = DateTime.ParseExact(dt, format,CultureInfo.InvariantCulture);
When I debug dt is coming in as 05/18/2011 09:25:17 AM but I get an expection saying:
String was not recognized as a valid
DateTime.
Starting off, you have no need for the conversion.
DateTime.FromFileTime(e8.sts[counter8].TimeStamp) returns a DateTime already...
Even so, with the string you have provided, DateTime.Parse(str) will take care of you.
If you end up storing this value in a text file, and really are dead-set on using a custom format string to parse it (which you don't need to):
The format you have:
Day/Month/Year 24-hour:minute:second
But looking at your input date:
05/18/2011 09:25:17 AM
You want:
Month/Day/Year 12-hour:minutes:seconds AM/PM
The format for what you want is:
MM/dd/yyyy hh:mm:ss tt
Isn't this expected? Date 05/18/2011 09:25:17 AM doesn't match your format string dd-MM-yyyy HH:mm:ss. Your date is in format MM/dd/yyyy HH:mm:ss tt.
Try this:
DateTime dateTime = DateTime.Parse("05/18/2011 09:25:17 AM");
I don't see any reason for the conversion. Just use:
DateTime.FromFileTime(e8.sts[counter8].TimeStamp)
Your DateTime is coming in as MM-dd-yyyy but you are trying to parse it as dd-MM-yyyy
Change your format string to "MM-dd-yyyy HH:mm:ss tt"
You can tell this as dt, using your current format string, is trying to be parsed as the 5th day (dd) of the 18th month (MM) of 2011 (yyyy)...
EDIT:
Sorry, I completely missed the AM/PM designator, you need the tt part of the format string. This will handle the AM/PM part of the string
EDIT 2:
As per your most recent comment, you want to convert it into MM-dd-yyyy HH:mm:ss string, the all you need to do is:
var outputString = DateTime.FromFileTime(e8.sts[counter8].TimeStamp).ToString("MM-dd-yyyy HH:mm:ss");
You already have the TimeStamp in a val;id .NET DateTime object, so all you need to do is perform a .ToString() with the required time format.
DateTime parsed = DateTime.ParseExact(dt,"MM/dd/yyyy HH:mm:ss tt",CultureInfo.InvariantCulture);
s many of the others have explained here, the format needs to be changed. However even when I tried the formats they have suggested, I still received the same error that you did. Eventually I hit upon the right format to get successful results.
The format should be:
string format = "MM/dd/yyyy HH:mm:ss tt";
because you are specifying time pattern such as AM. If the month is given as single digit, eg: 5, then MM should be replaced with M. I used slash instead of hypen between the dates because that's how the original date had been given.