How to parse DateTime - c#

How can I parse this DateTime value?
17-09-2018 3:18
I want to parse the date and the time.
This is what I've tried so far:
x = DateTime.ParseExact(dateString, "d/M/yyyy hh:MM",CultureInfo.InvariantCulture).ToString();
x = DateTime.ParseExact(dateString, "dd/MM/yyyy hh:MM",CultureInfo.InvariantCulture).ToString();
x = DateTime.ParseExact(dateString, "dd/MM/yyyy hh:MM",CultureInfo.InvariantCulture).ToString();
How can I make this work?

MM is months, mm is minutes. The casing matters.
Double m or double M means the value always has 2 digits. A single m or single M means the value can have 1 digit if below 10.
H means hours in military time (24 hour format), h means 12 hour with possible am/pm. The same rule applies for double digits.
The character used between values has to match the input string, don't specify - if you are using / or the other way around. Alternativly use a culture parameter that has the same format specifier as in the input string.
DateTime x = DateTime.ParseExact("17-09-2018 3:18", "d-MM-yyyy h:m", CultureInfo.InvariantCulture);
See also DateTime.ParseExact and Custom Date and Time Format Strings

You are almost there. You just need to remember two more things:
mm is for minutes and MM is for month.
It's better to use DateTime.TryParseExact and not let the program throw exception interrupting the flow unless that is intended.
// input string
string dateString = "5/01/2009 09:00";
// variable to hold output value
DateTime dateValue;
// specify all the valid formats here applicable in your case
string[] formats = { "dd/MM/yyyy hh:mm", "dd/M/yyyy hh:mm", "d/M/yyyy hh:mm", "d/MM/yyyy hh:mm", "dd/MM/yy hh:mm", "dd/M/yy hh:mm", "d/M/yy hh:mm", "d/MM/yy hh:mm"};
if (DateTime.TryParseExact(dateString, formats, CultureInfo.InvariantCulture,
DateTimeStyles.None, out dateValue))
Console.WriteLine("Converted '{0}' to {1} ({2}).", dateString, dateValue,
dateValue.Kind);

Related

Convert String to DateTime(yyyy-mm-dd)

I'm parsing date from server, date is in this format 6/16/2016 3:15:29 PM Could you help me please convert date to 2016-06-16?
I tried:
DateTime date = DateTime.ParseExact(datestring, "MM/dd/yyyy h-m-s t", System.Globalization.CultureInfo.InvariantCulture);
string formattedDate = date.ToString("yyyy-MM-dd")
but it's giving me error.
You've got 3 problems
You're not using the correct time separators
You're using only one t when you need two
You're using two M when you only need one
Try
DateTime date = DateTime.ParseExact(datestring, "M/d/yyyy h:m:s tt", System.Globalization.CultureInfo.InvariantCulture);
string formattedDate = date.ToString("yyyy-MM-dd");
The reason you need only one M is because MM expects a leading zero. Since the values of the date and time are delimited it's better to use the single versions for month, day, minutes, and seconds because they will work for values with or without leading zeros.
To execute DateTime.ParseExact() format of the input string and the format string must be the same. try this:
DateTime date = DateTime.ParseExact(datestring, "M/dd/yyyy h:mm:ss tt", System.Globalization.CultureInfo.InvariantCulture);
string formattedDate = date.ToString("yyyy-MM-dd");
These are interesting in the given input string(6/16/2016 3:15:29 PM):
The month is represented in single digit so it should be M instead for MM. We use MM if it is specified as 06.
Same in the case of Hours too. It should be h instead for normal hh
There is a single space in between Date and Time as well as Time and PM.
So we must consider all of these while generating the Format-string for ParseExact

converting an existing date to another date c#

Wanted to pass a string value of 8/26/2015 8:00:00 PM for conversion to
2015-08-26 20:00:00.000 in SQL.
But before I could do that,
string was not recognized as a valid datetime.
DateTime clock = Clockval.StartTime.Value.Add(Clock.StartTime.Value.TimeOfDay);
theStartTimeConvert = DateTime.ParseExact(clock.ToString(), "dd/MM/yyyy HH:mm:ss tt", null).ToString("MMM. dd, yyyy HH:mm:ss");
Did I pass in the wrong codes? And is there other alternatives to convert to 2015-08-26 20:00:00.000 from DateTime?
First of all the M custom format specifier represents the month as a number from 1 through 12. You use it to parse number 23.
Second, since your months and hours can have a single digit you should use M and H instead of MM and HH:
var str = "8/26/2015 8:00:00 PM";
var parsedDate = DateTime.ParseExact(str, "M/dd/yyyy h:mm:ss tt", CultureInfo.InvariantCulture);
var formattedDate = parsedDate.ToString("MMM. dd, yyyy HH:mm:ss");
If format works fine with my str, but doesn't work with your Clock.StartTime.Value.ToString(); - I guess you can have issue, that was desribed here. To cut the long story, sometimes strings isn't what you think is it. There a lot of Unicode characters which don't appear in the debug representation. Try to work with this string for parsing:
var str = Clock.StartTime.Value.ToString();
var correctDateStr= new String(str
.ToCharArray()
.Where(c => c <= 255)
.ToArray());

Converting string to DateTime failing

I have a string variable whose data will be the format below.
18-03-2015 16:39:15
i'm trying to convert it to a valid DateTime with hour/minute/second but so far the line below fails.
DateTime dt = DateTime.ParseExact("18-03-2015 16:39:15", "dd-MM-yyyy h:m:s", CultureInfo.InvariantCulture);
You need to use uppercase H or HH, so "dd-MM-yyyy HH:m:s" with this time: 16:39:15.
See: The "HH" Custom Format Specifier
So lowercase is from 1 through 12 and uppercase for 24h format. If you use H or HH depends on if 4:39:15 is possible or 04:39:15. A single H supports both formats, so with or without a leading zero, whereas HH only allows 04:39:15.
It should be HH:mm:ss in format
DateTime dt = DateTime.ParseExact("18-03-2015 16:39:15", "dd-MM-yyyy HH:mm:ss", CultureInfo.InvariantCulture);
// So: dt.ToString("dd-MM-yyyy HH:mm:ss") is 18-03-2015 16:39:15
Here are some examples of formatting the date with samples

convert string to datetime format invalid System.Datetime

I have been trying many different solutions found here but none works. I want to convert the string to the format of dd/MM/yyyy
editField["ExpiryTime"] = "5/19/2011 12:00:00 AM";
DateTime dt = DateTime.ParseExact(editField["ExpiryTime"].ToString(), "dd/MM/yyyy HH:mm:ss tt", CultureInfo.InvariantCulture);
But I always get an error of invalid System.DateTime. Pleaes help!
Use CultureInfo.InvariantCulture to avoid culture issues like invalid date separators and this format:
M/dd/yyyy hh:mm:ss tt
Uppercase M is for months, dd are the days, yyyy the four digit years. Lowercase hh are the hours in 12h format(required in combination with AM/PM), mm are the minutes, ss the seconds and tt the AM/PM designator.
string input = editField["ExpiryTime"].ToString(); // "5/19/2011 12:00:00 AM"
DateTime dt = DateTime.ParseExact(input, "M/dd/yyyy hh:mm:ss tt", CultureInfo.InvariantCulture);
I want to convert the string to the format of dd/MM/yyyy
Then use ToString in the same way, CultureInfo.InvariantCulture forces / as date separator, without it will be replaced with your current culture's date-separator:
string result = dt.ToString("dd/MM/yyyy", CultureInfo.InvariantCulture);
If you need it as string, then you should try this
var dt = string.Format("{0:dd/MM/yyyy}",DateTime.Now);
Note: Also check your local system date time format. If it mismatches with the used one , still you might experience the same exception..

DateTime.TryParse issue with dates of yyyy-dd-MM format

I have the following date in string format "2011-29-01 12:00 am" . Now I am trying to convert that to datetime format with the following code:
DateTime.TryParse(dateTime, out dt);
But I am alwayws getting dt as {1/1/0001 12:00:00 AM} , Can you please tell me why ? and how can I convert that string to date.
EDIT: I just saw everybody mentioned to use format argument. I will mention now that I can't use the format parameter as I have some setting to select the custom dateformat what user wants, and based on that user is able to get the date in textbox in that format automatically via jQuery datepicker.
This should work based on your example "2011-29-01 12:00 am"
DateTime dt;
DateTime.TryParseExact(dateTime,
"yyyy-dd-MM hh:mm tt",
CultureInfo.InvariantCulture,
DateTimeStyles.None,
out dt);
You need to use the ParseExact method. This takes a string as its second argument that specifies the format the datetime is in, for example:
// Parse date and time with custom specifier.
dateString = "2011-29-01 12:00 am";
format = "yyyy-dd-MM h:mm tt";
try
{
result = DateTime.ParseExact(dateString, format, provider);
Console.WriteLine("{0} converts to {1}.", dateString, result.ToString());
}
catch (FormatException)
{
Console.WriteLine("{0} is not in the correct format.", dateString);
}
If the user can specify a format in the UI, then you need to translate that to a string you can pass into this method. You can do that by either allowing the user to enter the format string directly - though this means that the conversion is more likely to fail as they will enter an invalid format string - or having a combo box that presents them with the possible choices and you set up the format strings for these choices.
If it's likely that the input will be incorrect (user input for example) it would be better to use TryParseExact rather than use exceptions to handle the error case:
// Parse date and time with custom specifier.
dateString = "2011-29-01 12:00 am";
format = "yyyy-dd-MM h:mm tt";
DateTime result;
if (DateTime.TryParseExact(dateString, format, provider, DateTimeStyles.None, out result))
{
Console.WriteLine("{0} converts to {1}.", dateString, result.ToString());
}
else
{
Console.WriteLine("{0} is not in the correct format.", dateString);
}
A better alternative might be to not present the user with a choice of date formats, but use the overload that takes an array of formats:
// A list of possible American date formats - swap M and d for European formats
string[] formats= {"M/d/yyyy h:mm:ss tt", "M/d/yyyy h:mm tt",
"MM/dd/yyyy hh:mm:ss", "M/d/yyyy h:mm:ss",
"M/d/yyyy hh:mm tt", "M/d/yyyy hh tt",
"M/d/yyyy h:mm", "M/d/yyyy h:mm",
"MM/dd/yyyy hh:mm", "M/dd/yyyy hh:mm",
"MM/d/yyyy HH:mm:ss.ffffff" };
string dateString; // The string the date gets read into
try
{
dateValue = DateTime.ParseExact(dateString, formats,
new CultureInfo("en-US"),
DateTimeStyles.None);
Console.WriteLine("Converted '{0}' to {1}.", dateString, dateValue);
}
catch (FormatException)
{
Console.WriteLine("Unable to convert '{0}' to a date.", dateString);
}
If you read the possible formats out of a configuration file or database then you can add to these as you encounter all the different ways people want to enter dates.
The main drawback with this approach is that you will still have ambiguous dates. The formats are tried in order so no matter what it'll try the European format before the American (or vice versa) and cover anything where the day is less than 13 to a European formatted date even if the user thought they were entering an American formatted date.
Try using safe TryParseExact method
DateTime temp;
string date = "2011-29-01 12:00 am";
DateTime.TryParseExact(date, "yyyy-dd-MM hh:mm tt", CultureInfo.InvariantCulture, DateTimeStyles.None, out temp);
From DateTime on msdn:
Type: System.DateTime% When this method returns, contains the DateTime
value equivalent to the date and time contained in s, if the
conversion succeeded, or MinValue 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.
This parameter is passed uninitialized.
Use parseexact with the format string "yyyy-dd-MM hh:mm tt" instead.
That works:
DateTime dt = DateTime.ParseExact("2011-29-01 12:00 am", "yyyy-dd-MM hh:mm tt", System.Globalization.CultureInfo.InvariantCulture);
DateTime dt = DateTime.ParseExact("11-22-2012 12:00 am", "MM-dd-yyyy hh:mm tt", System.Globalization.CultureInfo.InvariantCulture);
If you give the user the opportunity to change the date/time format, then you'll have to create a corresponding format string to use for parsing. If you know the possible date formats (i.e. the user has to select from a list), then this is much easier because you can create those format strings at compile time.
If you let the user do free-format design of the date/time format, then you'll have to create the corresponding DateTime format strings at runtime.

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