I have a windows service application in which I am getting the current date and time using DateTime.Now.ToString(), which returns '04-05-2018 05:50:12'.
But I tried the same in a sample console application, but it returns the date in a different format as '5/4/2018 5:51:32 AM'
Both these machines are being executed in the same machine. Can some one let me know why is there a date format difference in these applications?
The DateTime.ToString() formats the DateTime according to current culture. As Written in the Documentation
Converts the value of the current DateTime object to its equivalent
string representation using the formatting conventions of the current
culture.(Overrides ValueType.ToString().)
If you want the same string you should instead use the DateTime.ToString(string) overload and provide the exact format which you want.
The ToString(String) method returns the string representation of a
date and time value in a specific format that uses the formatting
conventions of the current culture; for more information, see
CultureInfo.CurrentCulture.
The format parameter should contain either a single format specifier
character (see Standard Date and Time Format Strings) or a custom
format pattern (see Custom Date and Time Format Strings) that defines
the format of the returned string. If format is null or an empty
string, the general format specifier, 'G', is used.
Some uses of this method include:
Getting a string that displays the date and time in the current
culture’s short date and time format. To do this, you use the “G”
format specifier.
Getting a string that contains only the month and year. To do this,
you use the “MM/yyyy” format string. The format string uses the
current culture’s date separator.
Getting a string that contains the date and time in a specific format.
For example, the “MM/dd/yyyyHH:mm” format string displays the date and
time string in a fixed format such as “19//03//2013 18:06". The format
string uses “/” as a fixed date separator regardless of
culture-specific settings.
Getting a date in a condensed format that could be used for
serializing a date string. For example, the "yyyyMMdd" format string
displays a four-digit year followed by a two-digit month and a
two-digit day with no date separator.
Related
Does following DateTime format "%M/%d/yyyy %H:%m:%s" will include both lines, e.g. with or without leading zero:
Line 1: 4/8/2022 7:6:3
Line 2: 04/08/2022 07:06:03
It's seems to be working but related documentation is more welcome.
The related documentation can be found here: https://learn.microsoft.com/en-us/dotnet/standard/base-types/custom-date-and-time-format-strings
Note the description of the % symbol: "Defines the following character as a custom format specifier".[1]
Since you have a custom date time format string, the symbols M, d, H, ... are custom format specifiers. This means, here % essentially becomes a no-operation without any effect, because the symbols following it are already custom format specifiers.
So, what exactly is the purpose of % if the symbols in a custom date time format string are already custom format specifiers regardless of % being there or not? The reason for % becomes understandable when you consider that there are also standard date time format strings, which consist of a single character, a single format specifier. Pertinent documentation here: https://learn.microsoft.com/en-us/dotnet/standard/base-types/standard-date-and-time-format-strings
Basically, any date time format string made of only one character is treated as a standard date time format string. And any date time format string with two or more characters is treated as a custom date time format string.
What if you want to use a custom date time format string consisting of only one custom format specifier? That one-character string will be interpreted as a standard date time format string instead. And that is a problem.
If you compare the lists of specifiers for standard and custom date time format strings, you'll notice that many of the standard date time format specifiers use symbols that are also used by custom date time format specifiers. However, standard date time format specifiers represent different data and/or formatting patterns than the respective custom date time format specifier using the same symbol. For example, the standard date time format specifier y yields year+month, while the custom date time format specifier y yields the last two digits of the year.
Therefore, if you need a functionally single-specifier custom date time format string, you gotta fatten up that string and turn it from a one-character string into a two-characters string with the help of the "no-op" specifier %, so that it will be correctly treated as a custom date time format string.
As an example, imagine you want to get just the last two digits of the year and nothing more, and you decide to use the custom format specifier y which does exactly what you want. However, the format string "y" is a standard date time format string yielding year+month. So, how do you get what you want? You turn the standard date time format string "y" into a custom date time format string by using "%y".
[1]According to that documentation, it should theoretically be possible to use contiguous sequences of multiple % in custom date time format string like "%%%%%M/%%%%%%d". Each of those % sequences should functionally collapse into a single %, as by definition according to the quoted documentation, each % defines the following % as a custom format specifier that it already is. However -- and for the better, i might add -- the DateTime formatting functions will have none of such shenanigans and throw a FormatException for you being a bad boy having even tried this...
I've created a webtest and have a CSV data source that contains a column with a list of short dates (MM/dd/yyyy)
I need to manipulate the parameter due to part of the web page I'm testing has a form parameter that needs it to be formatted as yyyyMMdd
When the date that is captured from the data source (ex: 02/12/2016), I noticed in the Context tab of my test run that the format to "2/12/2016 12:00:00 AM"
I've created a Request plug-in and added the following code:
public override void PreRequest(object sender, PreRequestEventArgs e)
{
base.PreRequest(sender e)
string CSVDate = e.WebTest.Context["<datasource date column>"].ToString();
DateTime dt = DateTime.ParseExact(CSVDate, "MM/dd/yyyy HH:mm:ss", System.Globalization.CultureInfo.InvariantCulture);
e.WebTest.Context.Add("NewDate", dt.ToString("yyyyMMdd"));
}
This generates a String was not recognized as a valid DateTime error. I tried changing the format to MM/dd/yyyy, but I encountered the same error.
Does anyone know how the correct DateTime format I should be using?
The date-time as shown in the context is 2/12/2016 12:00:00 AM. This has only one digit for the month whereas the format specifier has MM which wants two digits. The date-time also contains the letters AM that are not matched by the format.
Modifying the format to be M/dd/yyyy HH:mm:ss matches the date-time 2/12/2016 12:00:00, but does not match the AM part. In theory the tt format specifier should match this, but it did not work for me.
Rather than using ParseExact you can use Parse and it works out the correct format. Using the following worked on the date-time string provided:
DateTime dt1 = DateTime.Parse(CSVDate, new System.Globalization.CultureInfo("en-US"));
The CultureInfo is needed because the input date has the month and the days the wrong way around.
However, the real problem is in the way CSV files are handled by the web test. It appears to read them using the same logic as Microsoft Excel uses when reading CSVs. Namely, if it looks like a date then convert it to a date. So any string matching dd/dd/dddd (where d is a digit) might be connverted to a date. (E.g. 15/15/2017 will not be converted because 15 is not a month number.) I recommend rewriting the CSV to format the input date differently, use something that Excel would not treat as a date. One option is to have the date in three columns of the CSV, so have explicit day,monthandyearcolumns. Another option is to add non-date characters to the string and format it correctly, eg asz20160212and then remove thezwithin the web test. Generally, I would advise to avoid the conversion of string toDateTime` then another conversion to a different string.
the string is 20131024174621 which is year =2013, month=10, date=24, hours=17, minutes=46, seconds=21
What I am trying to do is to convert and format it into 2013-10-24 17:46:21.
I have tried my luck as the code below however it return such error :
String was not recognized as a valid DateTime.
String timestamp = "20131024174621";
String converted = DateTime.Parse(timestamp).ToString("yyyy-MM-dd HH:mm:ss");
What should be the way of doing it right?
You have to use ParseExact.
void Main()
{
String timestamp = "20131024174621";
var date = DateTime.ParseExact(timestamp, "yyyyMMddHHmmss", CultureInfo.InvariantCulture);
Console.WriteLine (date.ToString("yyyy-MM-dd HH:mm:ss"));
}
Output:
2013-10-24 17:46:21
DateTime.ParseExact( timestamp, "yyyyMMddHHmmss", CultureInfo.InvariantCulture ).ToString( "yyyy-MM-dd HH:mm:ss" );
Since other two answer is correct, I want to point the root of your problem.
DateTime.Parse method uses Standard Date and Time Format Strings. From How Standard Format Strings Work
In a formatting operation, a standard format string is simply an alias
for a custom format string. The advantage of using an alias to refer
to a custom format string is that, although the alias remains
invariant, the custom format string itself can vary. This is important
because the string representations of date and time values typically
vary by culture. For example, the "d" standard format string indicates
that a date and time value is to be displayed using a short date
pattern. For the invariant culture, this pattern is "MM/dd/yyyy". For
the fr-FR culture, it is "dd/MM/yyyy". For the ja-JP culture, it is
"yyyy/MM/dd"
In 20131024174621 string, you need yyyyMMddHHmmss format for your current culture. Looks like your culture doesn't have this format and that's why you get this error.
For this kind of non-standart format string, you can use custom date format.
Any string that is not a standard date and time format string is
interpreted as a custom date and time format string.
As I wrote in third paragraph, this kind of date formats is based on culture. When you have this kind of custom date strings, in most case using DateTime.ParseExact Method (String, String, IFormatProvider) with specific culture is the best choice.
I have a string that has a date stored in it.
String date = "03-05-2013 00:00:00";
I parsed it to Datetime as follows:
DateTime Start = DateTime.Parse(date);
Start.ToString() gave me "3/5/2013 12:0:00 AM"
I also used:
DateTime Start = DateTime.ParseExact(date,"dd-MM-yyyy HH:mm:ss",CultureInfo.InvariantCulture);
Then, Start.ToString() gave me "3/5/2013 12:0:00 AM", which is the exact same result as the previous one. I need to keep the original formatting. How may I do it? Thanks.
The format you parse with does not dictate how the DateTime is formatted when you convert the date back to a string. When you call ToString on a date it pulls the format from the current culture of the thread your code is executing on (which defaults to the culture of the machine your on).
You can override this by passing the format into ToString() i.e.
Start.ToString("dd-MM-yyyy HH:mm:ss", CultureInfo.InvariantCulture);
See Custom Date and Time Formats.
You need to pass the format in the ToString() call.
Start.ToString("dd-MM-yyy HH:mm:ss");
I need to keep the original formatting.
Then you need to apply the same pattern again when you call ToString:
string formatted = Start.ToString("dd-MM-yyyy HH:mm:ss",
CultureInfo.InvariantCulture);
(Note that you should specify the same culture when formatting as you did when parsing, to avoid things like the time separator from changing.)
Note that for some formats this still might not give the exact original representation - if you're using a format which includes the text for a month, for example, that would match case-insensitively, so input including "MARCH" would be reformatted as "March".
A DateTime value is just a date and time (and a "kind", but that's another story) - it doesn't maintain a textual representation any more than an integer does. It's important to differentiate between the inherent data in a value and a textual representation of that data. Most types which have multiple possible textual representations have no notion of keeping "the original representation" alongside the data.
I am currently in British summer time which is UTC +1 Hour. I confirmed my PC is correct with the following code and it returns true.
System.TimeZone.CurrentTimeZone.IsDaylightSavingTime(Date.Now)
My question is then why does the UTC formatter not work as I would expect:
DateTime.Now.ToString("u")
It returns the exact current system date as below in UTC format as expected but with the Z (Zulu Time) at the end not +01:00?
i.e.
2009-05-27 14:21:22Z
not
2009-05-27 14:21:22+01:00
Is this correct functionality?
MSDN states the following:
Represents a custom date and time format string defined by the DateTimeFormatInfo.UniversalSortableDateTimePattern property. The pattern reflects a defined standard and the property is read-only. Therefore, it is always the same, regardless of the culture used or the format provider supplied. The custom format string is "yyyy'-'MM'-'dd HH':'mm':'ss'Z'".
When this standard format specifier is used, the formatting or parsing operation always uses the invariant culture.
Formatting does not convert the time zone for the date and time object. Therefore, the application must convert a date and time to Coordinated Universal Time (UTC) before using this format specifier.
You should use the following code to convert your current Date to UTC before formatting it:
DateTime.UtcNow.ToString("u")
or
DateTime.Now.ToUniversalTime().ToString("u")
To display in the format you expected (i.e. 2009-05-27 14:21:22+01:00), you would need to use a custom date format:
DateTime.Now.ToString("yyyy-MM-dd HH:mm:sszzz");
"u" is the Universal sortable date/time pattern, not UTC format; To quote the documentation:
Represents a custom date and time format string defined by the DateTimeFormatInfo..::.UniversalSortableDateTimePattern property. The pattern reflects a defined standard and the property is read-only. Therefore, it is always the same, regardless of the culture used or the format provider supplied. The custom format string is "yyyy'-'MM'-'dd HH':'mm':'ss'Z'".
When this standard format specifier is used, the formatting or parsing operation always uses the invariant culture.
Formatting does not convert the time zone for the date and time object. Therefore, the application must convert a date and time to Coordinated Universal Time (UTC) before using this format specifier.
You need to use DateTime.Now.ToUniversalTime().ToString("u").