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Parsing a string like "03/2020" to a DateTime variable

I have to parse a string, which always look like 03/2020 (so the format is MM/yyyy), to a DateTime variable.
How do I achieve it the most proper way? (Without splitting the string into substrings)
I already found the DateTime.ParseExact function, but I'm confused by the third parameter (culture-specific format information).
Is the DateTime.ParseExact the way to go or is there a better function/way to achieve the goal?
var inputString = "03/2020";
var inputStringFormat = #"MM/yyyy";
// var inputStringAsDateTime = ???
Edit 1
As additional info I have to say, that the string (inputString) is read from a barcode. So the separator in it is always the /.
Tim Schmelter explained in his answer, how to mask such separators.
It looks like I have to change my inputStringFormat variable to:
var inputStringFormat = #"MM'/'yyyy";

If the first day of the month is good for you, you can use DateTime.ParseExact:
var d = DateTime.ParseExact(inputString, inputStringFormat, CultureInfo.InvariantCulture);

Usually, i use ToDateTime method of Convert class. I have tested it, it's working.
string inputString = "03/2020";
DateTime datetime = Convert.ToDateTime(inputString));
It will give output like 3/1/2020 12:00:00 AM means it will gives you output according to your system's date format.

With such simple date format you can use
var inputArr = inputString.split(#"/");
var inputStringAsDateTime = new DateTime(inputArr[0], inputArr[1], 1);
however for culture you can use constant
CultureInfo.InvariantCulture

Formatting any string to string "yyyy/MM/dd" [duplicate]

This question already has answers here:
Date formatting yyyymmdd to yyyy-mm-dd
(9 answers)
Closed 5 years ago.
I have many strings like "20120117" and "20120321". I need to convert it in a new string with this format: "2012/01/17" and "2012/03/21". So, there is a way to do this?
I try:
string dateString = string.format("{0:d", "20120321");
and
string dateString = string.format("{0:yyyy/MM/dd", "20120321");
and
string dateString = int.Parse("20120321").ToString("yyyy/MM/dd");
I all cases i don't reach my goal. =/
So, i can i do this?
OBS: There is a way to do that without parse to datetime?

You have to parse those values in DateTime objects first.
Example :
DateTime dt = DateTime.ParseExact("20120321", "yyyyMMdd", System.Globalization.CultureInfo.InvariantCulture);
var result = dt.ToString("yyyy/MM/dd");
Edit after your comments on other answers:
if you don't like parsing because it may throw excepations, you can always use TryParse, like this:
DateTime dt;
bool success = DateTime.TryParseExact("20120321", "yyyyMMdd", System.Globalization.CultureInfo.InvariantCulture, System.Globalization.DateTimeStyles.None, out dt);
if (success)
{
var result = dt.ToString("yyyy/MM/dd");
}
Edit 2: Using TryParseExact with multiple formats:
DateTime dt;
string[] formats = { "yyyyMMdd", "yyyy" };
bool success = DateTime.TryParseExact("20120321", formats, System.Globalization.CultureInfo.InvariantCulture, System.Globalization.DateTimeStyles.None, out dt);
if (success)
{
var result = dt.ToString("yyyy/MM/dd");
Console.WriteLine(result);
}
It will produce 2012/03/21 when using "20120321" as input value, and 2012/01/01 when using 2012 as input value.

DateTime.ParseExact("20120321", "yyyyMMdd", CultureInfo.CurrentCulture).ToString("yyyy/MM/dd")
You could parse the string but this method gives you validation without any extra code. Imagine receiving "20120230", "20110229", or any other invalid date.

From your comments:
There is a way to do that without parse to datetime?
Yes, absolutely. If you really want to propagate bad data through your system rather than highlighting that it's incorrect, you could definitely use:
// Make sure we'll always be able to get a result whatever the input.
string paddedInput = input + "????????";
string mightBeBadWhoKnows = string.Format("{0}/{1}/{2}",
paddedInput.Substring(0, 4), // The year, if we're lucky
paddedInput.Substring(4, 2), // The month, if we're lucky
paddedInput.Substring(6, 2)); // The day, if we're lucky
But why wouldn't you want to spot the bad data?
You absolutely should parse the data. If you want to be able to continue after receiving bad data having taken appropriate action, use DateTime.TryParseExact. If you're happy for an exception to be thrown, use DateTime.ParseExact. I'd suggest using the invariant culture for both parsing and formatting, unless you really want a culture-sensitive output.

Use DateTime.ParseExact to convert to a DateTime, then use ToString on that instance to format as you desire.
DateTime.ParseExact(dateString, "yyyyMMdd").ToString("yyyy/MM/dd");
EDIT: using Insert:
EDIT2: Fixed bugs :-)
var newString = dateString.Insert(4, "/").Insert(7, "/");

Just use string operations to insert the slashes:
string input = "20120321";
string dateString =
input.Substring(0, 4) + "/" +
input.Substring(4, 2) + "/" +
input.Substring(6);
or
string dateString = input.Insert(6, "/").Insert(4, "/");

If it's a date, try this:
DateTime.ParseExact("20120321","yyyyMMdd", null).ToString("yyyy/MM/dd", System.Globalization.DateTimeFormatInfo.InvariantInfo)

try this;
string dateString = DateTime.ParseExact("20120321", "yyyyMMdd",
null).ToShortDateString();

If your data is always in the same format and if you don't need to validate it, you can use the following snippet to avoid parsing it with DateTime
var strWithInsert = input.Insert(4,"/").Insert(7,"/");

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");

Trimming a string from Excel

I get a string from Excel as so: "\"11/01/2011 16:00\""
What's the most efficient way to trim this in C# so it can be parsed as a DateTime?

You could probably just trim the string, not sure how consistent that format will be though
var trimmedString = excelString.Trim('\\', '"');
That's assuming the string contains the slashes and those speech marks. If it's just the speech marks (because visual studio has escaped the string when displaying it) then all you need is
var trimmedString = excelString.Trim('"');

You don't need to trim it at all - you can just call DateTime.ParseExact or DateTime.TryParseExact which contains the quotes at each end:
string text = ...;
DateTime date = DateTime.ParseExact(text, "'\"'dd/MM/yyyy HH:mm'\"'",
CultureInfo.InvariantCulture);
I don't know whether that's more efficient than trimming (there's more parsing, but no extra string to create) but I would use it for its precision: if ever the data form changes (e.g. there's no longer a quote) you'll find out because you're stating your expectations, effectively.

string myString = "\"11/01/2011 16:00\"";
DateTime time = DateTime.Parse(myString.Substring(1, myString.Length - 2));

Always in that format? Can't you just substring the first 3 and last 3 characters and then Parse to a Date with a specific (supplied) date format?

s = s.Substring(1, s.Length-2);

You're looking for the parseExact method.
char[] trimChars = {'\"'};
string dateTime = "\"11/01/2011 16:00\"".Trim(trimChars);
DateTime result = DateTime.ParseExact(dateTime, "MM/dd/yyyy HH:mm", CultureInfo.InvariantCulture);

String was not recognized as a valid DateTime " format dd/MM/yyyy"

I am trying to convert my string formatted value to date type with format dd/MM/yyyy.
this.Text="22/11/2009";
DateTime date = DateTime.Parse(this.Text);
What is the problem ?
It has a second override which asks for IFormatProvider. What is this? Do I need to pass this also? If Yes how to use it for this case?
Edit
What are the differences between Parse and ParseExact?
Edit 2
Both answers of Slaks and Sam are working for me, currently user is giving the input but this will be assured by me that they are valid by using maskTextbox.
Which answer is better considering all aspects like type saftey, performance or something you feel like

Use DateTime.ParseExact.
this.Text="22/11/2009";
DateTime date = DateTime.ParseExact(this.Text, "dd/MM/yyyy", null);

You need to call ParseExact, which parses a date that exactly matches a format that you supply.
For example:
DateTime date = DateTime.ParseExact(this.Text, "dd/MM/yyyy", CultureInfo.InvariantCulture);
The IFormatProvider parameter specifies the culture to use to parse the date.
Unless your string comes from the user, you should pass CultureInfo.InvariantCulture.
If the string does come from the user, you should pass CultureInfo.CurrentCulture, which will use the settings that the user specified in Regional Options in Control Panel.

Parsing a string representation of a DateTime is a tricky thing because different cultures have different date formats. .Net is aware of these date formats and pulls them from your current culture (System.Threading.Thread.CurrentThread.CurrentCulture.DateTimeFormat) when you call DateTime.Parse(this.Text);
For example, the string "22/11/2009" does not match the ShortDatePattern for the United States (en-US) but it does match for France (fr-FR).
Now, you can either call DateTime.ParseExact and pass in the exact format string that you're expecting, or you can pass in an appropriate culture to DateTime.Parse to parse the date.
For example, this will parse your date correctly:
DateTime.Parse( "22/11/2009", CultureInfo.CreateSpecificCulture("fr-FR") );
Of course, you shouldn't just randomly pick France, but something appropriate to your needs.
What you need to figure out is what System.Threading.Thread.CurrentThread.CurrentCulture is set to, and if/why it differs from what you expect.

Although the above solutions are effective, you can also modify the webconfig file with the following...
<configuration>
<system.web>
<globalization culture="en-GB"/>
</system.web>
</configuration>
Ref : Datetime format different on local machine compared to production machine

You might need to specify the culture for that specific date format as in:
Thread.CurrentThread.CurrentCulture = new CultureInfo("en-GB"); //dd/MM/yyyy
this.Text="22/11/2009";
DateTime date = DateTime.Parse(this.Text);
For more details go here:
http://msdn.microsoft.com/en-us/library/5hh873ya.aspx

Based on this reference, the next approach worked for me:
// e.g. format = "dd/MM/yyyy", dateString = "10/07/2017"
var formatInfo = new DateTimeFormatInfo()
{
ShortDatePattern = format
};
date = Convert.ToDateTime(dateString, formatInfo);

After spending lot of time I have solved the problem
string strDate = PreocessDate(data);
string[] dateString = strDate.Split('/');
DateTime enter_date = Convert.ToDateTime(dateString[1]+"/"+dateString[0]+"/"+dateString[2]);

private DateTime ConvertToDateTime(string strDateTime)
{
DateTime dtFinaldate; string sDateTime;
try { dtFinaldate = Convert.ToDateTime(strDateTime); }
catch (Exception e)
{
string[] sDate = strDateTime.Split('/');
sDateTime = sDate[1] + '/' + sDate[0] + '/' + sDate[2];
dtFinaldate = Convert.ToDateTime(sDateTime);
}
return dtFinaldate;
}

use this to convert string to datetime:
Datetime DT = DateTime.ParseExact(STRDATE,"dd/MM/yyyy",System.Globalization.CultureInfo.CurrentUICulture.DateTimeFormat)

Just like someone above said you can send it as a string parameter but it must have this format: '20130121' for example and you can convert it to that format taking it directly from the control. So you'll get it for example from a textbox like:
date = datetextbox.text; // date is going to be something like: "2013-01-21 12:00:00am"
to convert it to: '20130121' you use:
date = date.Substring(6, 4) + date.Substring(3, 2) + date.Substring(0, 2);
so that SQL can convert it and put it into your database.

Worked for me below code:
DateTime date = DateTime.Parse(this.Text, CultureInfo.CreateSpecificCulture("fr-FR"));
Namespace
using System.Globalization;

You can use also
this.Text = "22112009";
DateTime newDateTime = new DateTime(Convert.ToInt32(this.Text.Substring(4, 4)), // Year
Convert.ToInt32(this.Text.Substring(2,2)), // Month
Convert.ToInt32(this.Text.Substring(0,2)));// Day

Also I noticed sometimes if your string has empty space in front or end or any other junk char attached in DateTime value then also we get this error message