Convert.DateTime - c#

What Convert.DateTime will convert the date 7/25/2010 12:00:00 it's current format is(MM/dd/yyyy HH:mm:ss)?
When I convert this string format to date time I am getting the error "string was not recognized as valid DateTime"

None. Dates are not stored internally as a certain format.
If you want to parse a string into a date, use DateTime.ParseExact or DateTime.TryParseExact (the former will throw an exception if the conversion fails, the second uses an out parameter):
DateTime myDate = DateTime.ParseExact("7/25/2010 12:00:00",
"MM/dd/yyyy HH:mm:ss",
CultureInfo.InvariantCulture);
If you want to display a certain format, use ToString with the format string.
So, if you have a date object that represents midday of the 25th of July 2010 (doesn't matter how it is represented internally) and you want to format it with the format string "MM/dd/yyyy HH:mm:ss" you do the following:
string formattedDate = myDate.ToString("MM/dd/yyyy HH:mm:ss");

If you need to use Convert.DateTime, I'll assume you're working with a string you want to convert to a date. So you might try this:
DateTime date = Convert.DateTime("7/25/2010 12:00:00 am");
string formattedDateString = date.ToString("MM/dd/yyyy HH:mm:ss")
I'm making no assumptions as to why you'd want to do this, except that, well, you have your reasons.

DateTime.TryParse() or DateTime.Parse() will do the trick.
Edit: This is assuming that you are going from a string to a DateTime object.
Edit2: I just tested this with your input string, and I receive no error with DateTime.Parse

Related

Inconsistency when parsing DateTime in the same format

I have the following strings:
10/10/2021 00:00:00 and 18/11/2021 23:59:59
I have this code:
bool first = DateTime.TryParse("10/10/2021 00:00:00",
CultureInfo.InvariantCulture,
DateTimeStyles.None,
out DateTime firstDate);
bool second = DateTime.TryParse("18/11/2021 23:59:59",
CultureInfo.InvariantCulture,
DateTimeStyles.None,
out DateTime secondDate);
Console.WriteLine(firstDate + " --- " + secondDate);
The output is:
10/10/2021 12:00:00 AM --- 1/1/0001 12:00:00 AM
As you can see the second date is not properly parsed, even though it's in the same format. What is the reason for that and how can I fix it?
As you can see the second date is not properly parsed, even though it's in the same format.
Here my two cents.
Programming languages and frameworks are not smart enough to know which kind of format data you applied, specially for dates, times, numbers etc.. If you provide these data, you kinda have to provide the proper format as well so they can do their job. You "said" the same format, but you didn't apply any format in your code. So, as we humans, we know (at least you told us) but the computer don't know.
Let's look what TryParse(String, IFormatProvider, DateTimeStyles, DateTime) documentation says;
Converts the specified string representation of a date and time to its
DateTime equivalent using the specified culture-specific format
information and formatting style, and returns a value that indicates
whether the conversion succeeded.
You didn't supply format information you supplied IFormatProvider as InvariantCulture. So, what are these "culture specific formats"?
Well, most of them are returns with GetAllDateTimePatterns method (but not all of them) but be aware because documentation says;
You can use the custom format strings in the array returned by the
GetAllDateTimePatterns method in formatting operations. However, if
you do, the string representation of a date and time value returned in that formatting operation cannot always be parsed successfully by the
Parse and TryParse methods. Therefore, you cannot assume that the
custom format strings returned by the GetAllDateTimePatterns method
can be used to round-trip date and time values.
So, if you run;
CultureInfo.InvariantCulture.DateTimeFormat.GetAllDateTimePatterns().Dump();
*Dump is just an extension method of LINQPad by the way, it just outputs to the console.
You will get a lot of datetime patterns, but for our case, the important one is we get MM/dd/yyyy HH:mm:ss format for InvariantCulture.
As you can see, your 18/11/2021 23:59:59 data doesn't match with MM/dd/yyyy HH:mm:ss format because there is no 18th month on Gregorian calendar which is a DateTime instance belongs internally.
Your second parsing fails by the way, that's quite different just saying "the second date is not properly parsed" and this is how DateTime.TryParse method works as explained in the documentation;
When this method returns, contains the DateTime value equivalent to
the date and time contained in s, if the conversion succeeded, or
MinValue (which is 1/1/0001 12:00:00 AM) if the conversion failed. The conversion fails if the s
parameter is null, is an empty string (""), or does not contain a
valid string representation of a date and time.
So, best way to handle this to supply a "specific" format using with DateTime.TryParseExact method or one of its overloads like;
bool first = DateTime.TryParseExact("10/10/2021 00:00:00",
"dd/MM/yyyy HH:mm:ss",
CultureInfo.InvariantCulture,
DateTimeStyles.None,
out DateTime firstDate);
bool second = DateTime.TryParseExact("18/11/2021 23:59:59",
"dd/MM/yyyy HH:mm:ss",
CultureInfo.InvariantCulture,
DateTimeStyles.None,
out DateTime secondDate);
The default DateTime format is 'MM/dd/yyyy' and since you have the date in 'dd/MM/yyyy' format it gives you the output.
Maybe try changing the date format input as 11/18/2021 23:59:59

Error converting DateTime to string format yyyy-MM-dd

I'm trying to convert some DateTime values to string format yyyy-MM-dd. The problem is i only need the date but in my case model.StartDate contains both date and time. When declaring model.StartDate as string "start" looks like this: 4/1/2014 12:00:00 AM. I get this error when trying to parse:
System.FormatException was unhandled by user code Message=String was
not recognized as a valid DateTime.
My best guess is that the error occurs because string contains both Date and Time but i could be wrong. If i explore model.StartDate further i can also find Day, DayOfTheWeek etc. Is this the right approach? I just want to convert model.StartDate to string "start" with format yyyy-MM-dd.
Heres my code:
string start = model.StartDate.ToString();
model.StartDate = DateTime.ParseExact(start, "yyyy-MM-dd", CultureInfo.InvariantCulture);
string end = model.EndDate.ToString();
model.EndDate = DateTime.ParseExact(end, "yyyy-MM-dd", CultureInfo.InvariantCulture);
Dunno what the problem is, might be that start contains time? I have no idea.
The model.StartDate and model.EndDate are DateTime properties from the view model:
[NopResourceDisplayName("Admin.GAStatistics.GAStatistics.StartDate")]
[UIHint("DateNullable")]
public DateTime? StartDate { get; set; }
[NopResourceDisplayName("Admin.GAStatistics.GAStatistics.EndDate")]
[UIHint("DateNullable")]
public DateTime? EndDate { get; set; }
EDIT:
Iv'e uploaded a image here showing the actual output i'm getting in the debugger:
https://imageshack.com/i/1n51u2p
Thank you
You are converting the dates to string but you don't specify the format. Try
string start = model.StartDate.ToString("yyyy-MM-dd);
ToString() uses the current thread's Culture format to convert the date to a string, including the time. The format used is G, the general date and time format.
Just for this format, you don't need to specify CultureInfo.InvariantCulture because there isn't anything culture specific. A common gotcha with the yyyy/MM/dd format though is that some cultures use - as the date specifier, and / is the date placeholder. In such a case you would have to use:
string start = model.StartDate.ToString("yyyy-MM-dd,CultureInfo.InvariantCulture);
UPDATE
From the comments, it seems that model.StartDate and model.EndDate are not DateTime objects but strings with a specific format that include a time element.
What you are actually trying to do is parse the original string to a DateTime object, then format this object to the new format string:
var date=DateTime.ParseExact(model.StartDate,"M/d/YYYY HH:mm:ss tt",
CultureInfo.InvariantCulture);
model.StartDate=date.ToString("yyyy-MM-dd",CultureInfo.InvariantCulture);
assuming the string the value "4/1/2014 12:00:00 AM" for April 1, 2014
You appear to be misunderstanding how ParseExact works (or actually what it does). Parsing, in general, is the process of taking data of type X and converting it to type Y - in the context of DateTime this means converting a date string to a DateTime instance. This is completely different to what you are trying to do which is formatting a DateTime instance.
Given you already have the date you don't need to parse anything, all you need to do is format the date
model.StartDate.ToString("yyyy-MM-dd", CultureInfo.InvariantCulture);
CultureInfo.InvariantCulture is important when working with fixed formats because you want to make sure you aren't culture aware i.e. the format you specify is exactly how you want it to display in all cultures.
Use the .Date property of a DateTime to get only the Date part. Your ToString() will also yield different results based on the current culture meaning that while your ToString() and then TryParse might work for you right now, it will break in other countries.
You can use ToString() overload to specify a specific format. Different formats can be found here

Format Exception - string not recognized as a valid DateTime

I have an issue similar to this > Format exception String was not recognized as a valid DateTime
However, my spec requires a date format of ddMMyyyy, therefore I have modified my code but I am still getting the same error
DateTime now = DateTime.Now;
DateTime dt = DateTime.ParseExact(now.ToString(), #"ddMMyyyy", CultureInfo.InvariantCulture);
I am unclear why.
You code fails because you are attempting to parse a date in the format ddMMyyyy, when by default DateTime.ToString() will produce a format with both date and time in the current culture.
For myself in Australia that would be dd/MM/yyy hh:mm:ss p e.g. 11/10/2013 11:07:03 AM
You must realise is that the DateTime object actually stores a date as individual components (e.g. day, month, year) that only needs to be format when you output the value into whatever format you desire.
E.g.
DateTime now = DateTime.Now;
string formattedDate = now.ToString("ddMMyyyy", DateTimeFormatInfo.InvariantInfo);
For more information see the api doc:
http://msdn.microsoft.com/en-us/library/8tfzyc64.aspx
For ParseExact to work, the string coming in must match exactly the pattern matching. In the other question you mentioned, the text was coming from a web form where the format was specified to be exactly one format.
In your case you generated the date using DateTime.Now.ToString() which will not be in the format ddMMyyyy. If you want to make the date round trip, you need to specify the format both places:
DateTime now = DateTime.Now;
DateTime dt = DateTime.ParseExact(now.ToString("ddMMyyyy"), #"ddMMyyyy", CultureInfo.InvariantCulture);
Debug your code and look at what the result of now.ToString() is, it's is not in the format of "ddMMyyyy", which is why the parse is failing. If you want to output now as a string in the ddMMyyy format, then try now.ToSTring("ddMMyyyy") instead.
now.ToString() does not return a string formatted in that way. Try using now.ToString("ddMMyyyy").
You might be better off testing with a static string like "30041999"

DateTime formats C#

I have a string which needs to be converted and validated to a DateTime. The string is in the following format 'dd.mm.yy'
I am trying to convert it to DateTime using the following
string format = "dd.mm.yy";
date = DateTime.ParseExact(current.Substring(aiRule.AiLength), format,
CultureInfo.InvariantCulture);
but unfortunately this fails.
The question is how to convert a string in the format 'dd.mm.yy' to a DateTime ?
Thank you
mm means "minutes". I suspect you want "dd.MM.yy". See MSDN for more information about custom date and time format strings.
(In particular, read the part about the "yy" specifier and how it chooses which century to use. If you can possibly change the input to use a four digit year, that could save you some problems...)
the string format should be like this....
string Format = "dd.MM.yy"
mm is for showing minutes
MM is for showing months..
I hope it will helps you...
As earlier posts has already pointed out, mm means minutes and MM means months. I ran this test snippet and it works as expected:
string format = "dd.MM.yy";
string date = "27.10.11";
DateTime result;
result = DateTime.ParseExact(date, format, CultureInfo.InvariantCulture);
I'll tell something "heretical". If dd.MM.yy (with 2 or 4 yy) is the format of your local culture, then you could let the DateTime.Parse (not ParseExact!) do its work without setting it to CultureInfo.InvariantCulture, or perhaps setting it to your local culture like new CultureInfo("it-IT").

Trying to parse a DateTime in C#

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.

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