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c# - Converting dd/mm/yyyy formatted string to Datetime


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You need to use DateTime.ParseExact with format "dd/MM/yyyy"

DateTime dt=DateTime.ParseExact("24/01/2013", "dd/MM/yyyy", CultureInfo.InvariantCulture);

Its safer if you use d/M/yyyy for the format, since that will handle both single digit and double digits day/month. But that really depends if you are expecting single/double digit values.


Your date format day/Month/Year might be an acceptable date format for some cultures. For example for Canadian Culture en-CA DateTime.Parse would work like:

DateTime dt = DateTime.Parse("24/01/2013", new CultureInfo("en-CA"));

Or

System.Threading.Thread.CurrentThread.CurrentCulture = new CultureInfo("en-CA");
DateTime dt = DateTime.Parse("24/01/2013"); //uses the current Thread's culture

Both the above lines would work because the the string's format is acceptable for en-CA culture. Since you are not supplying any culture to your DateTime.Parse call, your current culture is used for parsing which doesn't support the date format. Read more about it at DateTime.Parse.


Another method for parsing is using DateTime.TryParseExact

DateTime dt;
if (DateTime.TryParseExact("24/01/2013", 
                            "d/M/yyyy", 
                            CultureInfo.InvariantCulture, 
                            DateTimeStyles.None,
    out dt))
{
    //valid date
}
else
{
    //invalid date
}

The TryParse group of methods in .Net framework doesn't throw exception on invalid values, instead they return a bool value indicating success or failure in parsing.

Notice that I have used single d and M for day and month respectively. Single d and M works for both single/double digits day and month. So for the format d/M/yyyy valid values could be:

  • "24/01/2013"
  • "24/1/2013"
  • "4/12/2013" //4 December 2013
  • "04/12/2013"

For further reading you should see: Custom Date and Time Format Strings


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