Hi I have a string in following format 23/03/2014 and I have tried to convert it to this format:
string npacked = Convert.ToDateTime(packeddate).ToString("yyyy/MM/dd");
But I am getting an error:
String was not recognized as a valid DateTime
Also tried this:
string npacked = DateTime.Parse(packeddate).ToString("yyyy/MM/dd");
but same error.
try with ParseExact with the format
string npacked = DateTime.ParseExact(packeddate, "dd/MM/yyyy", CultureInfo.InvariantCulture).ToString("yyyy/MM/dd");
DEMO
Convert.ToDateTime is running a DateTime.Parse() on your string (23/03/2014). In the default culture (en-US) that is going to fail, since dates in that culture should be formatted MM/DD/YYYY. You need to switch to a different culture (like French) per MSDN:
// Reverse month and day to conform to the fr-FR culture.
// The date is February 16, 2008, 12 hours, 15 minutes and 12 seconds.
dateString = "16/02/2008 12:15:12";
try {
dateValue = DateTime.Parse(dateString);
Console.WriteLine("'{0}' converted to {1}.", dateString, dateValue);
}
catch (FormatException) {
Console.WriteLine("Unable to convert '{0}'.", dateString);
}
// Call another overload of Parse to successfully convert string
// formatted according to conventions of fr-FR culture.
try {
dateValue = DateTime.Parse(dateString, new CultureInfo("fr-FR", false));
Console.WriteLine("'{0}' converted to {1}.", dateString, dateValue);
}
catch (FormatException) {
Console.WriteLine("Unable to convert '{0}'.", dateString);
}
Calling "ToString" afterwards has no effect whatsoever on the parse attempt, it just formats the output of the parse.
It may be due to your system date time format. You have mm-dd-yyyy format in your system and you are trying to parse it in dd-mm-yyyy format. Try changing your system date format to dd/MM/yyyy.
Convert.ToDateTime(string) calls DateTime.Parse(string, CultureInfo.CurrentCulture) explicitly. That means your both lines are equivalent.
In your profile, it says you are from Dubai, United Arab Emirates. That's why I assume your CurrentCulture is probably ar-AE at first but your string matches it's ShortDatePattern and that's why it prints;
Convert.ToDateTime("23/03/2014", new CultureInfo("ar-AE")) // 23/03/2014
But you didn't tell us what is your CurrentCulture, we never know.. But looks like your current culture's date seperator is not / or your current culture doesn't have standart date format dd/MM/yyyy (which is unlikely for most of cultures) your both lines fail (first scenario is more likely).
You can easly parse your string with a culture that has / as a DateSeparator using DateTime.ParseExact method. This method let's you specify your custom date formats. We can use InvariantCulture for example;
var date = DateTime.ParseExact("23/03/2014",
"dd/MM/yyyy",
CultureInfo.InvariantCulture);
Now, let's consider to it's representation with yyyy/MM/dd format.
/ specifier has a special meaning of "replace me with the current culture's date separator" in custom date formats. That means if your date seperator is not / (I assume it is not) your date.ToString("yyyy/MM/dd") results will be included your date seperator, not /.
For example, I'm from Turkey, my culture is tr-TR. My date seperator is . (dot) That's why this example;
date.ToString("yyyy/MM/dd"); // Prints 2014.03.23 not 2014/03/23
In such a case, you can use a culture which has / a date seperator as a second parameter in your ToString method (InvariantCulture for example) like;
date.ToString("yyyy/MM/dd", CultureInfo.InvariantCulture) // Prints 2014/03/23
or you can escape your / character regardless which culture you use like;
date.ToString(#"yyyy\/MM\/dd") // Prints 2014/03/23
Related
I'm new to c# how can I convert my input string in to DateTime.
_toDate = 5/22/2015
I cannt use
DateTime.ParseExact(_toDate, "yyyy-MM-dd", null);
Or
Convert.ToDateTime(_toDate)
throw an exception String was not recognized as a valid DateTime.
Note : String shold be excact the same as above.
Appreciate your reply
Clearly, your string and format does not match.
From documentation;
Converts the specified string representation of a date and time to its
DateTime equivalent. The format of the string representation must
match a specified format exactly.
You need to use M/dd/yyyy with a culture that has / as a DateSeparator like InvariantCulture .
string _toDate = "5/22/2015";
DateTime myDate = DateTime.ParseExact(_toDate, "M/dd/yyyy", CultureInfo.InvariantCulture);
When you use null as an IFormatProvider, it's threaded as your CurrentCulture and if your CurrentCulture doesn't have / as a DateSeparator, you will get FormatException because / custom format specifier has a special meaning as replace me with current culture or supplied culture date separator.
I am working on an ASP.NET Mvc application with C# and facing a problem when I try to upload a .CSV file in order to save its data to database.
The problem comes from the date column of the .CSV file. There are two formats of date used in that column. The first one is "mm/dd/yyyy" that I have no problem to parse to a DateTime object by the following code:
// for the date : 09/30/2014
DateTime tempo = Convert.ToDateTime("09/30/2014");
The second format is "mm/dd/yy". The same method above doesn't work for this format and throws an exception
// for the date : 09/30/14
DateTime tempo = Convert.ToDateTime("09/30/14");
// this line throws ;
// [09/30/14] String was not recognized as a valid DateTime. exception
Is there a solution which works for both of date formats ?
Thanks for your help.
First, mm specifier is for minutes, MM specifier is for months. Convert.ToDateTime method uses your CurrentCulture by default. That means MM/dd/yy is not a standard date and time format your CurrentCulture but MM/dd/yyyy is.
You can use custom date and time formatting string like;
string s = "09/30/14";
DateTime date;
if(DateTime.TryParseExact(s, "MM/dd/yy", CultureInfo.InvariantCulture,
DateTimeStyles.None, out date))
{
// Successfully parse
}
Be aware "/" custom format specifier has a special meaning of replace me with the current culture or supplied culture date separator. That means even if your string and format matches, you parsing will fail.
Is there a solution which works for both of date formats ?
DateTime.TryParseExact method has an overload that takes formats as a string array. If your string matches one of your formats, it will returns true.
string s = "09/30/14";
sstring[] formats = {"MM/dd/yy", "MM/dd/yyyy"};
DateTime date;
if(DateTime.TryParseExact(s, formats, CultureInfo.InvariantCulture,
DateTimeStyles.None, out date))
{
// Successfully parse
}
Also you can see all standard date and time patters of your CurrentCulture like;
foreach (var format in CultureInfo.CurrentCulture.
DateTimeFormat.
GetAllDateTimePatterns())
{
Console.WriteLine (format);
}
I want to convert the date time to "MM/dd/yyyy" and when i am converting to this format the date is getting like "xx-xx-xxxx". I have written code like
var format = "MM/dd/yyyy HH:mm";
DateTime dt = DateTime.Now;
var dateString = dt.toString(format); // the value i am getting is 05-28-2014 12:47 but i require the 'dateString' value to be `05/28/2014 12:53`.
What is the issue with that.
Your currrent culture's date-separator seems to be - that's why you get it. You have to specify InvariantCulture:
string dateString = dt.toString("MM/dd/yyyy HH:mm", CultureInfo.InvariantCulture);
See: The "/" Custom Format Specifier
The "/" custom format specifier represents the date separator, which
is used to differentiate years, months, and days. The appropriate
localized date separator is retrieved from the
DateTimeFormatInfo.DateSeparator property of the current or specified
culture.
Another way is to escape the / with \:
string dateString = dt.toString(#"MM\/dd\/yyyy HH\:mm");
But in my opinion, if you already know the special meaning of / as "current culture's date-separator", it's better(in terms of readability) to use the correct CultureInfo (or InvariantCulture) instead.
This depends on your current culture date-separator. Try to include InvariantCulture as follows:
var dateStringFormat= dt.toString("MM/dd/yyyy HH:mm", CultureInfo.InvariantCulture);
Another way from #TimSchmelter's answer is to escape special symbols / and : so they are not treated as day and time separators.
var dateString = dt.toString(#"MM\/dd\/yyyy HH\:mm");
you will specified the format while converting date and time i.e. DateTime.Now.ToString("MM/dd/yyyy hh:mm ss tt")
for more ref.
http://msdn.microsoft.com/en-us/library/system.datetime.aspx
I have a excel sheet in which am taking a date column in this format "23/8/11 01:33:01:PM"
and am inserting it in sql 2008 using datarow but am getting a error
String was not recognised as valid datetime.
Can any one please help?
DateTime newdate = Convert.ToDateTime(row[8].ToString());
Here how Convert.ToDateTime method looks like when you decompile it;
public static DateTime ToDateTime(string value)
{
if (value == null)
return new DateTime(0L);
else
return DateTime.Parse(value, (IFormatProvider) CultureInfo.CurrentCulture);
}
As you can see, this method use DateTime.Parse method with your CurrentCulture. And if your string doesn't match your current culture date format, your code will be broken. That's the reason you get this error.
Use DateTime.ParseExact with "dd/M/yy hh:mm:ss:tt" format instead.
Converts the specified string representation of a date and time to its
DateTime equivalent. The format of the string representation must
match a specified format exactly or an exception is thrown.
string s = "23/8/11 01:33:01:PM";
DateTime newdate = DateTime.ParseExact(s, "dd/M/yy hh:mm:ss:tt", CultureInfo.InvariantCulture);
Console.WriteLine(newdate);
Output will be;
8/23/2011 1:33:01 PM
Here a DEMO.
For your case;
DateTime newdate = DateTime.ParseExact(row[8].ToString(), "dd/M/yy hh:mm:ss:tt", CultureInfo.InvariantCulture);
For more informations, take a look;
Custom Date and Time Format Strings
Convert.ToDateTime internally calls DateTime.Parse which by default will use the current culture of your application. If 23/8/11 01:33:01:PM is not a valid format for this culture then this method will fail.
For specific date formats it's best to use DateTime.ParseExact e.g.
DateTime.ParseExact("23/8/11 01:33:01:PM", "dd/M/yy hh:mm:ss:tt", CultureInfo.InvariantCulture);
This approach makes your code culture independent which means the date will always be parsed correctly (given it's in the specified format).
This will work:
DateTime newdate = Convert.ToDateTime("8/23/11 01:33:01 PM");
I changed day and month and removed the colon a the end. But that is very specific. You need to know more about the dates passed to do that.
I have a date string in format "08/1999" I want to get the first date of the corresponding month. eg : in this case 08/01/1999.
It is simple for en-Us culture. I break the string, append "01" in the string to get 08/01/1999 and then DateTime.Parse(datestring) but this is valid for en-US culture only.
How can I do this for different culture ?
My datestring will always be in mm/yyyy format. and I am trying to obtain a DataTime obj from this dateString.
Use ParseExact method. Note upper-cased M's are for months and lower-cased m's for minutes.
string dateToConvert = "08/1999";
string format = "MM/yyyy";
CultureInfo provider = CultureInfo.InvariantCulture;
DateTime result = DateTime.ParseExact(dateToConvert, format, provider);
Output:
{1999-08-01 00:00:00}
You can also use Convert.ToDateTime and Parse methods. It will produce the same result, but in implicite way:
DateTime result = Convert.ToDateTime(dateToConvert, provider); // Output: {1999-08-01 00:00:00}
DateTime result = DateTime.Parse(dateToConvert, provider); // Output: {1999-08-01 00:00:00}
Read more at:
Parsing Date and Time Strings
Standard Date and Time Format Strings
Custom Date and Time Format Strings
I'm not sure if I understand your question correctly, but you can try passing CultureInfo.InvariantCulture if you want to force the US date format regardless of the regional settings of the client computer:
DateTime.Parse("08/1999", System.Globalization.CultureInfo.InvariantCulture)
I break the string, append "01" in the string to get 08/01/1999 and then DateTime.Parse(datestring)
That's a very long-winded way to do it. Simply this will work:
DateTime.Parse("08/1999")
How can I do this for different culture ?
If your string is always in this format, do this:
DateTime.Parse("08/1999", CultureInfo.InvariantCulture)