I am using the code below to check the datetime and it is working fine in my machine but once after deployment, I am getting
"String was not recognized as a valid DateTime."
Please provide me the solution to work in all machine.
DateTime date1 = DateTime.Parse("16/05"); MM/dd
string todaydate = DateTime.Now.ToString("MM/dd");
if (Convert.ToDateTime(todaydate) > Convert.ToDateTime(date1.ToString("MM/dd")))
{ //Logic }
Honestly, since both answer didn't satisfied me, here is my two cent..
Let's look at your code line by line;
DateTime date1 = DateTime.Parse("16/05");
DateTime.Parse uses your CurrentCulture settings by default if don't provide any IFormatProvider as a second parameter on it's overloads. That means, if your one of standard date and time patterns of your CurrentCulture includes dd/MM (or your current culture DateSeparator since / format separator has a special meaning of replace me with current culture date separator) format, this parsing operation will be successful. That means this line might throws FormatException that depends on the current culture settings.
string todaydate = DateTime.Now.ToString("MM/dd");
DateTime.Now returns a local current time. With it's ToString() method you try to get it's string representation with MM/dd format. BUT WAIT! You used / format specifier again and still, you didn't use any IFormatProvider. Since this format specifier replace itself with current culture date separator, your todaydate might be 05/16, 05-16 or 05.16. That's totally depends on what date separator your current culture use.
Convert.ToDateTime(todaydate)
Convert.ToDateTime method uses DateTime.Parse explicitly. That means,since you didn't provide any IFormatProvider it will be use your CurrentCulture again and it's standard date and time formats. As I said, todaydate might be 05/16, 05-16 or 05.16 as a result. But there is no guarantee that your current culture parse this string successfully because it may not have MM/dd in it's standard date and time formats. If it parse "16/05" successfully, that means it has dd/MM format, in such a case, it definitely can't have MM/dd as a standard date and time format. A culture can't parse dd/MM and MM/dd formats at the same time. In such a case, it can't know that 01/02 string should parse as 2nd January or 1st February, right?
Convert.ToDateTime(date1.ToString("MM/dd"))
Same as here. As todaydate string, this will create "05/16" (it depends on current culture date separator of course) result and still there is no guarantee to parse this successfully.
And as said in comments, there is no point to parse your string to DateTime and get it's same string representation as well.
I strongly suspect you try to compare your current date is bigger than your parsed DateTime or not, you can use DateTime.Today property to compare with it. This property gets DateTime as current date part plus midnight as time part. For example;
DateTime dt;
if(DateTime.TryParseExact("16/05", "dd/MM", CultureInfo.InvariantCulture,
DateTimeStyles.None, out dt))
{
if(DateTime.Today > dt)
{
// Your operation
}
}
DateTime dt = DateTime.ParseExact("16/05", "dd/MM", CultureInfo.InvariantCulture);
if (DateTime.Today > dt)
{
// your application logic
}
DateTime dt = // From whatever source
if (DateTime.Now.Ticks > dt.Ticks)
{
// Do logic
}
Related
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
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
i have date stored in a string format as follows: "2014-03-12"
im passing this to a database which accepts the date as datetime.
im converting the string date to datetime format as follows:
DateTime StartDates = Convert.ToDateTime(StartDate);
but the time gets appended along with the date as "2014-03-12 12:00:00:00"
can anyone tel me how to send only the date leaving out the time.
i want the final date to be still in datetime format only but with time part cut off
DateTime is irrespective of the format. Formatting is only useful for presentation purpose. A DateTime object will have a Date part and Time part. When you try parsing your string "2014-03-12", it doesn't have a Time part, so in the parsed object, Time is set to 00:00:00.
If you just want to to display date then you can use DateTime.ToShortDateString method or use a custom format like:
string formattedDateString = StartDates.ToString("yyyy-MM-dd", CultureInfo.InvariantCulture);
If you're happy with the date part, you may simply return the Date property of the DateTime conversion result:
DateTime StartDates = Convert.ToDateTime(StartDate).Date;
I should mention that using Convert.ToDateTime puts you at the mercy of the process current culture date format though, so you probably want to use the ParseExact or ToString method like the other answers suggests, with the appropriate format and culture instance.
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"
I have a string in my DB2 database which is physically located in US. I have a column value set to this string '2011-12-31 00:00:00' which indicates year 2011, month december and day 1st of the december.
I'm retrieving this as a string in my client program which is running in UK and the UI is set to local culture(the default). My client program also runs in US as well as in Hongkong with the culture set to the local culture there i.e US and HK respectively.
I'm using the following code for parsing the string into a datetime. I'm not very sure whether this is going to work, and I could't find any good link which points me to that direction. Could you please tell me whether this will work in various cultures, if not why?
string quarterStartDate = "2011-12-01 00:00:00";
DateTime quarterStart;
DateTime.TryParse(quarterStartDate, CultureInfo.InvariantCulture, DateTimeStyles.None, out quarterStart);
return quarterStart;
I have a test which works as per my requirement, but again 'am not too sure whether this will work when the UI is going to run in a different country.
string quarterStarter = "2011-12-01 00:00:00";
DateTime quarterStart;
DateTime.TryParse(quarterStarter,CultureInfo.InvariantCulture,DateTimeStyles.None,out quarterStart);
Assert.IsTrue(quarterStart.Year == 2011);
Assert.IsTrue(quarterStart.Month == 12);
Assert.IsTrue(quarterStart.Day == 1);
I would strongly suggest that as you know the format in advance, you use TryParseExact instead of TryParse:
bool success = DateTime.TryParseExact(quarterStarter, "yyyy-MM-dd HH:mm:ss",
CultureInfo.InvariantCulture,
DateTimeStyles.None,
out quarterStart);
Note that you should check the return value of TryParseExact to check that it's parsed correctly - if you're fine with an exception, just use ParseExact instead.
It's entirely possible that your existing code would work just fine - after all, you're already providing the invariant culture - but specifying the format makes it clearer what you really expect, and also means you'll detect if a value in an unexpected format is provided.
You can use ParseExact to pull the date, for example:
var s = "2011-12-01 00:00:00";
var dt = DateTime.ParseExact(s,"yyyy-MM-dd HH:mm:ss",CultureInfo.InvariantCulture);
You can set a specific format that does not change with culture.
DateTime dt;
DateTime.TryParseExact(dateTime,
"yyyy-MM-dd hh:mm tt",
CultureInfo.InvariantCulture,
DateTimeStyles.None,
out dt);