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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 Date To convert DateTime using ParseExact

I have a string and it comes as a DD/MM/YYYY style.(eg : 11/07/2018)
I need to convert this To DateTime format and YYYY-MM-DD style.
I tried it using DateTime.Parse but can't
if (!String.IsNullOrEmpty(fromDate))
{
frm = DateTime.ParseExact(fromDate, "yyyy-MM-dd", CultureInfo.InvariantCulture, DateTimeStyles.None);
}
else if(!String.IsNullOrEmpty(toDate))
{
todt = DateTime.ParseExact(toDate, "yyyy-MM-dd", CultureInfo.InvariantCulture, DateTimeStyles.None);
}

You can do this in one line of code.
var newDateString = DateTime.ParseExact(myDateString, "dd/MM/yyyy", CultureInfo.InvariantCulture, DateTimeStyles.None).ToString("yyyy-MM-dd");
Keep in mind that a DateTime instance is a data structure that does not have a format. When dealing with dates and times it is best to only revert to a human readable string when you need to present/output the value for a human to read. For anything else including persistence to a storage system that supports types (like a relational database) leave the value as a DateTime type.
Example: If you wanted yyyy-MM-dd because you wanted to persist this to Sql Server then you should stop after the parsing (and not call ToString). You can then assign the DateTime instance to a command parameter's Value property directly.

Convert using ParseExact and then use ToString to the target format:
string dateS = "30/04/2018";
DateTime dateD = DateTime.ParseExact(dateS, "dd/MM/yyyy", System.Globalization.CultureInfo.InvariantCulture);
string dateS2 = dateD.ToString("yyyy-MM-dd");
Here is a working example in fiddle: https://dotnetfiddle.net/e0yuZ6

DateTime.TryParseExact only working in "One Way"

Scope:
I have been trying to develop a super-tolerant DateTime.Parse routine, so I decided to give most "widely-used" formats a try to better understand the format masks.
Problem:
I have defined a specific format (String) which I use as myDate.ToString(format), and it works wonders. The problem is, If I get this same String (result of the .ToString(format) operation), and feed it back to DateTime.TryParseExact (...) it fails.
Code / Test:
System.Globalization.CultureInfo provider = System.Globalization.CultureInfo.InvariantCulture;
// Defining Format and Testing it via "DateTime.ToString(format)"
string format = "MM/dd/yyyy HH:mm:ss tt";
string dtNow = DateTime.Now.ToString (format);
Console.WriteLine (dtNow);
// Trying to Parse DateTime on the same Format defined Above
DateTime time;
if (DateTime.TryParseExact (dtNow, format, provider, System.Globalization.DateTimeStyles.None, out time))
{
// If TryParseExact Worked
Console.WriteLine ("Result: " + time.ToString ());
}
else
{
// If TryParseExact Failed
Console.WriteLine ("Failed to Parse Date");
}
Output is : "Failed to Parse Date".
Question:
Why can I use the format string to format a certain date as text, but I can't use the same format to feed the string back to a date object ?
EDIT:
I have added part of my method to this example, and I would like to know why the "ParseDate" method fails to return a proper date, given that the "String" is in the right format.

Since you use DateTime.ToString() method without any IFormatProvider, this method will use your CurrentCulture settings.
That's why your
string dtNow = DateTime.Now.ToString (format);
line might generate a different string representation than MM/dd/yyyy HH:mm:ss tt format.
Three things can cause this issue;
Your CurrentCulture has a different DateSeparator than /
Your CurrentCulture has a different TimeSeparator than :
Your CurrentCulture has a different or empty string as a AMDesignator and/or PMDesignator
Since you try to parse your string with provider (which is InvariantCulture) on your DateTime.TryParseExact method, generate your string based on that provider as well.
string dtNow = DateTime.Now.ToString(format, provider);
You told your CurrentCulture is pt-BR and this culture has empty string "" as a AMDesignator and PMDesignator. That's why your dtNow string will not have any AM or PM designator on it's representation part.
Here a demonstration.

Convert string into mm/dd/yyyy format

I have following strings in different formats:
16/05/2014
21-Jun-2014
2014-05-16
16-05-2014
5/19/2014
14 May 2014
I need to convert all the above strings into mm/dd/yyyy format in c#.
I have tried used DateTime.ParseExact as DateTime dt = DateTime.ParseExact("16-05-2014", "mm/dd/yyyy hh:mm:ss tt", CultureInfo.InvariantCulture) in C# but i am getting the exception as "String was not recognized as a valid DateTime".
I have also tried to use to Convert.ToDateTime() but it is also not working.
Is there any method or function that we can write/available in C# that would convert the above string formats into a single date format i.e into "mm/dd/yyyy" format ??
Any help on this would be greatly appreciated.

It fails on the very first term of your format string, which is telling the function to treat the "16" as minutes and to look for hours, minutes, and seconds that don't exist in the input.
You have several different date formats, and so need the ParseExact() overload that accepts several different format strings:
string[] formats= {"dd/MM/yyyy", "dd-MMM-yyyy", "yyyy-MM-dd",
"dd-MM-yyyy", "M/d/yyyy", "dd MMM yyyy"};
string converted = DateTime.ParseExact("16-05-2014", formats, CultureInfo.InvariantCulture, DateTimeStyles.None).ToString("MM/dd/yyyy");
Also remember that lower case "m"s are for minutes. If you want months, you need an upper case "M". Full documentation on format strings is here:
http://msdn.microsoft.com/en-us/library/8kb3ddd4.aspx
Finally, I suspect you are getting ahead of yourself on formatting the output as a string. Keep these values as DateTime objects for as long as possible, and only format to a string at the last possible moment before showing them to the user. If you really do want a string, at least stick with the ISO 8601 standard format.

Your main problem is that your format string is wrong. A small m is for minute, a big M is for month.
Try to pass all your formats in an array. For example like this
DateTime.ParseExact("16-05-2014",
new[] {"dd/MM/yyyy", "dd-MMM-yyyy", "yyyy-MM-dd",
"dd-MM-yyyy", "M/d/yyyy", "dd MMM yyyy"},
CultureInfo.InvariantCulture, DateTimeStyles.None);
With this you can parse all your formats at once.
For more information about the format settings, see the official docs.

Few things:
Your input date 16/05/2014 doesn't match your format Month/Day/Year - how can there be a 16th month?
Secondly, you're using mm which represents Minutes, not Months. You should use MM.
Finally, your sample string 16-05-2014 doesn't match the format provided, you've used hyphens - instead of forward slashes /
Supply a collection of different formats matching your input:
string[] formats = new [] { "MM/dd/yyyy", "dd-MMM-yyyy",
"yyyy-MM-dd", "dd-MM-yyyy", "dd MMM yyyy" };
DateTime dt = DateTime.ParseExact("05-16-2014", formats, CultureInfo.InvariantCulture, DateTimeStyles.None);

You might find the following method useful to accept whatever date format you want and convert it to DateTime:
public DateTime? DTNullable(string DateTimestring, string CurrDateTimeFormat)
{
if (string.IsNullOrEmpty(DateTimestring)) return null;
else
{
DateTime datetimeNotNull;
DateTime.TryParseExact(DateTimestring, CurrDateTimeFormat, null, System.Globalization.DateTimeStyles.None, out datetimeNotNull);
return datetimeNotNull;
}
}
Pass in your desired string to be converted to DateTime along with it's current date time format and this would return you a nullable DateTime. If you're certain that whatever string you're passing in won't be null then you can remove that bit. The reason for it being there is that you can't convert a null to DateTime. In my case I couldn't be certain if it would be or not so I needed the ability to capture nulls as well.
You can use it like this:
DateTime? MyDateTime = DTNullable(MyStartDate, "dd/MM/yyyy");
If you wanted you could alter the method to accept an array of strings and simply iterate through each and return them all in a list if they were of the same format.
As others have pointed out, months are MM not mm (minutes).

On a DateTime object you can call .ToString("MM/dd/yyyy"). Given the strings you have, you can first create new DateTime objects for each string and then call .ToString("MM/dd/yyyy"). For example:
var dateAsMmDdYyyy = DateTime.Now.ToString("MM/dd/yyyy");

string represents date, and reformat it

The following case:
There is a string that has this format "2012-02-25 07:53:04"
But in the end, i rather want to end up with this format "25-02-2012 07:53:04"
I think i have 2 options. 1 would be to reformat the string and move it all around, but i dont think this is a clean way of doing this.
A other way that i was thinking about is to save the source string to a date parameter, and then write the date parameter back to a string in a certain date format.
But is this even possible to do ?

Do this:
DateTime.Parse("2012-02-25 07:53:04").ToString("dd-MM-yyyy hh:mm:ss");
Keep in mind this isn't culture-aware. And if you do need to store the intermediate result you could do that just as easily:
var myDate = DateTime.Parse("2012-02-25 07:53:04");
var myDateFormatted = myDate.ToString("dd-MM-yyyy hh:mm:ss");
Lastly, check out TryParse() if you can't guarantee the input format will always be valid.

Others have suggested using Parse - but I'd recommend using TryParseExact or ParseExact, also specifying the invariant culture unless you really want to use the current culture. For example:
string input = "2012-02-25 07:53:04";
DateTime dateTime;
if (!DateTime.TryParseExact(input, "yyyy-MM-dd HH:mm:ss",
CultureInfo.InvariantCulture,
DateTimeStyles.None,
out dateTime))
{
Console.WriteLine("Couldn't parse value");
}
else
{
string formatted = dateTime.ToString("dd-MM-yyyy HH:mm:ss",
CultureInfo.InvariantCulture);
Console.WriteLine("Formatted to: {0}", formatted);
}
Alternatively using Noda Time:
string input = "2012-02-25 07:53:04";
// These can be private static readonly fields. They're thread-safe
var inputPattern = LocalDateTimePattern.CreateWithInvariantInfo("yyyy-MM-dd HH:mm:ss");
var outputPattern = LocalDateTimePattern.CreateWithInvariantInfo("dd-MM-yy HH:mm:ss");
var parsed = inputPattern.Parse(input);
if (!parsed.Success)
{
Console.WriteLine("Couldn't parse value");
}
else
{
string formatted = outputPattern.Format(parsed.Value);
Console.WriteLine("Formatted to: {0}", formatted);
}

Parse as DateTime then reformat it. Be careful: use always an IFormatProvider!

Yes, it is quite possible. All you need to do is use DateTime.Parse to parse the string into a DateTime struct and then use ToString() to write the date back out to another string with the format you want.

You can parse this as a date object and then provide the formatting you want when using the date.ToString method:
date.ToString("dd-MM-yyyy hh:mm:ss");

Yes, you can use custom DateTime format strings to parse and reformat DateTime objects.
DateTime date = DateTime.ParseExact("2012-02-25 07:53:04", "yyyy-MM-dd HH:mm:ss", CultureInfo.InvariantCulture);
string formattedDated = date.ToString("dd-MM-yyyy HH:mm:ss");