Develop Reference

How to convert this UTC datetime string to DateTime object c#

I have been trying to convert this string to a DateTime object in C#
2019-09-23T08:34:00UTC+1
I've tried using DateTime.Parse but it is throwing an exception for
"String was not recognized as a valid DateTime."

I'm sorry but you seem like a victim of garbage in, garbage out.
That's an unusual format, that's why before I suggest a solution for you, first thing I want to say is "Fix your input first if you can".
Let's say you can't fix your input, then you need to consider a few things;
First of all, if your string has some parts like UTC and/or GMT, there is no custom date and time format specifier to parse them. That's why you need to escape them as a string literal. See this question for more details.
Second, your +1 part looks like a UTC Offset value. The "z" custom format specifier is what you need for parse it but be careful, this format specifier is not recommended for use with DateTime values since it doesn't reflect the value of an instance's Kind property.
As a solution for DateTime, you can parse it like I would suggest;
var s = "2019-09-23T08:34:00UTC+1";
DateTime dt;
if(DateTime.TryParseExact(s, "yyyy-MM-dd'T'HH:mm:ss'UTC'z", CultureInfo.InvariantCulture,
DateTimeStyles.AdjustToUniversal, out dt))
{
Console.WriteLine(dt);
}
which gives you 2019-09-23 07:34:00 as a DateTime and which has Utc as a Kind property.
As a solution for DateTimeOffset - since your string has a UTC Offset value you should consider to parse with this rather than Datetime
-, as Matt commented, you can use it's .DateTime property to get it's data like;
var s = "2019-09-23T08:34:00UTC+1";
DateTimeOffset dto;
if(DateTimeOffset.TryParseExact(s, "yyyy-MM-dd'T'HH:mm:ss'UTC'z", CultureInfo.InvariantCulture,
DateTimeStyles.None, out dto))
{
Console.WriteLine(dto.DateTime);
}
which gives you the same result DateTime but Unspecified as a .Kind property.
But, again, I strongly suggest you to fix your input first.

Use TryParseExact to convert the string to datetime. Here is the sample code to covert the given format(s) to datetime
private static DateTime ParseDate(string providedDate) {
DateTime validDate;
string[] formats = {
"yyyy-MM-ddTHH:mm:ss"
};
var dateFormatIsValid = DateTime.TryParseExact(
providedDate, formats, CultureInfo.InvariantCulture, DateTimeStyles.None, out validDate);
return dateFormatIsValid ? validDate: DateTime.MinValue;
}
Then, use this function to convert the string. I am replacing UTC+1 to empty string
static void Main(string[] args) {
string strdatetime = "2019-09-23T08:34:00UTC+1";
DateTime dateTime = ParseDate(strdatetime.Replace("UTC+1", ""));
Console.WriteLine(dateTime);
}

String to Date parsing

I am getting a string and i want to parse that string as date and want to store it in DataTable.
string can be in formats
1- "2014/23/10"
2- "2014-23-10"
{
string st="2014/23/10";
string st="2014-23-10";
}
And attach time with it.
Any idea to make it possible ?

DateTime.ParseExact or DateTime.TryParseExact are appropriate here - both will accept multiple format strings, which is what you need in this case. Make sure you specify the invariant culture so that no culture-specific settings (such as the default calendar) affect the result:
string[] formats = { "yyyy-MM-dd", "yyyy/MM/dd" };
DateTime date;
if (DateTime.TryParseExact(input, formats,
CultureInfo.InvariantCulture,
DateTimeStyles.None, out date))
{
// Add date to the DataTable
}
else
{
// Handle parse failure. If this really shouldn't happen,
// use DateTime.ParseExact instead
}
If the input is from a user (and is therefore "expected" to be potentially broken, without that indicating an error anywhere in the the system), you should use TryParseExact. If a failure to parse indicates a significant problem which should simply abort the current operation, use ParseExact instead (it throws an exception on failure).

Since both are not standart date and time format, you can use DateTime.ParseExact method like;
string st = "2014/23/10";
string st1 = "2014-23-10";
var date = DateTime.ParseExact(st,
"yyyy/dd/MM", CultureInfo.InvariantCulture);
var date1 = DateTime.ParseExact(st1,
"yyyy-dd-MM", CultureInfo.InvariantCulture);
Output will be;
10/23/2014 12:00:00 AM
10/23/2014 12:00:00 AM
Here a demonstration.
Of course these outputs depends your current culture thread.
If you want to format your DateTime's as a string representation, you can use DateTime.ToString(string) overload which accepts as a string format.
Since you have more than one format, you can use DateTime.TryParseExact(String, String[], IFormatProvider, DateTimeStyles, DateTime) overload which is takes your formats as a string array.
var formats = new []{"yyyy-MM-dd", "yyyy/MM/dd"};
DateTime dt;
if(DateTime.TryParseExact(st, formats, CultureInfo.InvariantCulture, DateTimeStyles.None, out dt))
{
//
}
else
{
//
}

Convert to a DateTime with DateTime.TryParseExact(); or even DateTime.Parse if you need to be flexible. Then you can format it back out however you like!
See: http://msdn.microsoft.com/en-us/library/ms131044(v=vs.110).aspx

Try
DateTime.Parse(st, CultureInfo.InvariantCulture, DateTimeStyles.AdjustToUniversal);
Set DateTimeStyles based on your requirement.

Try this:
DateTime.Parse(st);
If It the above line not works for you, then add cultrureInfo below:
DateTime.ParseExact(st,"yyyy/dd/MM", CultureInfo.InvariantCulture);

converting messy date string to dateTime object in c#

How can I convert the String 20120313 to a DateTime object that holds the value 13-Mar-2012?
I fetch it as
DataEffectiveDate = Convert.ToDateTime(reader["date_id"]);
But it fails here already (converting to 1/1/2001)

You need to use DateTime.ParseExact:
DateTime date = DateTime.ParseExact(text, "yyyyMMdd",
CultureInfo.InvariantCulture);
Then if you want it as "13-Mar-2012", you need:
string reformatted = date.ToString("dd-MMM-yyyy");
... optionally passing in whatever culture you want to use for the month names etc.
(Another alternative is to use my Noda Time, which allows you to parse this as just a local date, without any concerns about what time it will use, time zones etc.)

When you have a particular format in mind, ParseExact is helpful:
string s = "20120313";
var when = DateTime.ParseExact(s, "yyyyMMdd", CultureInfo.InvariantCulture);
There's also an overload that accepts multiple candidate formats.

Try DateTime.ParseExact:
string date = DateTime.ParseExact(reader["date_id"], "yyyyMMdd", new CultureInfo("en"));

Retaining MM/DD/YYYY format in String

I need to write date in MM/DD/YYYY format. From a Date Picker Control. I try to assign it to a DateTime variable. Before Writing it to a file I assign it to a string. I see the value stored in String variable is in DD/MM/YYYY format.
Below is assignment statement
DateTime startTime, endTime;
string startTimeDate = "";
startTime = Convert.ToDateTime(dpStartTime.Value.ToString("MM/dd/yyyy HH:mm"));
endTime = Convert.ToDateTime(dpEndTime.Value.ToString("MM/dd/yyyy HH:mm"));
startTimeDate = startTime.ToString("MM/dd/yyyy HH:mm");
startTimeDate = startTimeDate.Replace('-', '/');
I observe startTimeDate is stored as DD/MM/YYYY only. startTime is storing as MM/DD/YYYY format only. Please let me know if there is any other approach to correctly assign / convert the date values.
Thanks in Advance

Edit:
You are losing the original date in your Convert.DateTime() conversion, you have to apply the format string here as well e.g. using DateTime.ParseExact :
startTime = DateTime.ParseExact(dpStartTime.Value.ToString("MM/dd/yyyy HH:mm"),
"MM/dd/yyyy HH:mm",
CultureInfo.InvariantCulture);

Instead of using Convert.ToDateTime(), try to use DateTime.ParseExact(string s, string format, IFormatProvider provider) when you can ensure the datetime format and want to ignore the system settings. MSDN Reference for the DateTime.ParseExact() method can be found here

You're converting DateTime to string, then you're converting it again to DateTime using Convert class. You're not preserving the format here cause DateTime is format agnostic. And default ToString conversion (used by debugger) is in your cause MM/DD/YYYY.

I usually use String.Format, ex
String.Format("{0:d/M/yyyy HH:mm:ss}", dpStartTime.Value);
To format dates as strings.

DateTime - How can i account for different delimiter characters

My application is taking the time now, formatting it into a string, and parsing it back to a valid DateTime value using ParseExact. See below for more details:
DateTime dt = DateTime.Now;
DateTime timeNow = DateTime.Now;
string timeStamp = dt.ToString("MM/dd/yyyy HH:mm:ss");
// To match different countries
if (timeStamp.IndexOf("/") > -1)
{
timeNow = DateTime.ParseExact(timeStamp, "MM/dd/yyyy HH:mm:ss", System.Globalization.CultureInfo.InvariantCulture);
}
else if (timeStamp.IndexOf(".") > -1)
{
timeNow = DateTime.ParseExact(timeStamp, "MM.dd.yyyy HH:mm:ss", System.Globalization.CultureInfo.InvariantCulture);
}
Different countries use different date formats. Is there a way to make my application automatically take into account the different formats, rather than having to make a condition for each one that appears?
Thanks for any help,
Evan

If your application is using a string representation for dates internally, I would suggest using the Sortable format specifier when outputting it. That way, you always know that you can read it back using ParseExact and the "s" format specifier.
The only time you should output dates in any other format is when you need to display them for the user, or when some other program requires them in a particular format.
As #Mike Christensen pointed out in his comment, different locales will interpret dates differently. The default output for many European countries is DD/MM/YYYY, whereas in the U.S. it's usually MM/DD/YYYY. If you take the different locales into account, then there will be ambiguity.

You can pass an array of format specifiers with as many formats as you want to support.
string[] formats = new [] { "MM/dd/yyyy HH:mm:ss", "MM.dd.yyyy HH:mm:ss" };
DateTime d = DateTime.ParseExact
(
timestamp, formats,
CultureInfo.InvariantCulture,
DateTimeStyles.None);
However, since you say you are generating the strings yourself, why don't you just make sure you always format them using the InvariantCulture:
string timestamp = dt.ToString("MM/dd/yyyy HH:mm:ss",
CultureInfo.InvariantCulture);