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DateTime.TryParse() not working with formatted date dd/MM/yyyy

This code returns (min time 1/1/0001 12:00:00 AM) not Date.Time.Now . Try Parse works for MM/dd/yyyy but not dd/MM/yyyy . Any suggestions
Here is code
DateTime start, end;
DateTime.TryParse(EPSDate12.Text, out start);
string TNow = DateTime.Now.ToString("dd/MM/yyyy HH:mm:ss"); // Works
// string TNow = DateTime.Now.ToString();// works but gives MM/dd/yyyy as expected
DateTime.TryParse(TNow, out end); // No. gives min time (1/1/0001 12:00:00 AM)

Use TryParseExact and supply the format string.
Also examine the return value from TryParseExact to know if it failed or not (it returns a bool)
I see "EPSDate12.Text" which i suspect may be a TextBox: If you're doing this in a UI, make life easy and use a DateTimePicker - you can set the format, the user can type into them just like a textbox, but they don't accept invalid inputs, and all you have to do is get the .Value property which gives you a DateTime
As to why your attempts to parse the string you made don't work, I think it most likely that the date format Parse is using (which is based on the culture settings of the executing thread) is not the same format as the string you prepared using your forced format. Either make sure your forced format is matched to the current culture, or use a culture that matches your forced format, or use [Try]ParseExact to force the format for parsing like you did when creating the string
See https://learn.microsoft.com/en-us/dotnet/api/system.datetime.parse?view=net-5.0#Culture for more info

The datetime value is internally the same. But, ToString() return value, depends on
the local machine culture setup.
Reference article
The default DateTime.ToString() method returns the string
representation of a date and time value using the current culture's
short date and long time pattern. The following example uses the
default DateTime.ToString() method.
For en-US culture(MM/dd/yyyy hh:mm:ss) , it will be in
7/28/2021 11:37:40 AM
If you want to see in en-GB(dd/MM/yyyy hh:mm:ss), you can apply conversion as given below:
var culture = new CultureInfo("en-GB");
MessageBox.Show($"{DateTime.Now.ToString(culture)}");
28/07/2021 11:45:09 AM
you can also specify exact custom format, in which you want to display.
MessageBox.Show($"{DateTime.Now.ToString("dd/MM/yyyy HH:mm:ss tt")}");
28/07/2021 11:45:09 AM

Thanks for suggestions . Yes DateTime.TryParse is not working and it could be format issue
This line of code.
string TNow = DateTime.Now.ToString("dd/MM/yyyy HH:mm:ss");
generates
29/07/2021 14:49:03
which looks OK but fails TryParse

Datetime Formatting giving it a specific culture doesn't change how day is printed out

Is DateTime format strictly dependent on the language of the OS being used? Because the following doesn't work:
DateTime date = DateTime.Now;
var usCultureInfo = CultureInfo.CreateSpecificCulture("en-US");
Console.WriteLine(date.ToString("dddd MM-dd-yy"),usCultureInfo);
I'd like the result to print out as Saturday, 06-29-2013 but the day gets printed out in Korean 토요일, 06-29-2013.

You are a victim of Composite Formatting overload for Console.WriteLine where you could pass Format string and a series of object to be inserted in the placeholders of the format string
You need to write in this way
Console.WriteLine(date.ToString("dddd MM-dd-yy",usCultureInfo));
and you get the right day text.
See the specs here DateTime.ToString(format, IFormatProvider)

Or simply you can use
string abc=date.ToString("dddd MM-dd-yy");

Convert date in string to DateTime with same format

I have a string that has a date stored in it.
String date = "03-05-2013 00:00:00";
I parsed it to Datetime as follows:
DateTime Start = DateTime.Parse(date);
Start.ToString() gave me "3/5/2013 12:0:00 AM"
I also used:
DateTime Start = DateTime.ParseExact(date,"dd-MM-yyyy HH:mm:ss",CultureInfo.InvariantCulture);
Then, Start.ToString() gave me "3/5/2013 12:0:00 AM", which is the exact same result as the previous one. I need to keep the original formatting. How may I do it? Thanks.

The format you parse with does not dictate how the DateTime is formatted when you convert the date back to a string. When you call ToString on a date it pulls the format from the current culture of the thread your code is executing on (which defaults to the culture of the machine your on).
You can override this by passing the format into ToString() i.e.
Start.ToString("dd-MM-yyyy HH:mm:ss", CultureInfo.InvariantCulture);
See Custom Date and Time Formats.

You need to pass the format in the ToString() call.
Start.ToString("dd-MM-yyy HH:mm:ss");

I need to keep the original formatting.
Then you need to apply the same pattern again when you call ToString:
string formatted = Start.ToString("dd-MM-yyyy HH:mm:ss",
CultureInfo.InvariantCulture);
(Note that you should specify the same culture when formatting as you did when parsing, to avoid things like the time separator from changing.)
Note that for some formats this still might not give the exact original representation - if you're using a format which includes the text for a month, for example, that would match case-insensitively, so input including "MARCH" would be reformatted as "March".
A DateTime value is just a date and time (and a "kind", but that's another story) - it doesn't maintain a textual representation any more than an integer does. It's important to differentiate between the inherent data in a value and a textual representation of that data. Most types which have multiple possible textual representations have no notion of keeping "the original representation" alongside the data.

How to convert MM/dd/yyyy to yyyy/MM/dd in C# using globalization

I have a text box in which a user is supposed to enter a date in MM/dd/yyyy format. This date is stored as yyyy/MM/dd in the database.
I want the user to enter the date in MM/dd/yyyy format and later I want to convert it to yyyy/mm/dd so that I can query the database.
How can I convert the user input date MM/dd/yyyy to yyyy/mm/dd?

If you're certain of the input string's format, use DateTime.ParseExact specifying "MM/dd/yyyy", then return the DateTime using .ToString with the appropriate "yyyy/MM/dd" format string.
There's no need to reference anything in the System.Globalization namespace for this.
That said, your database should be storing dates with a datetime format, rather than a string, in which case the format doesn't matter as your DBMS should do the conversion for you.

You can parse the date and format the result:
string str = Date.Parse(myDate).ToString("yyyy/MM/dd");
Alternatively, if the current culture doesn't support that date format and you've already validated the input:
string items[] = myDate.Split('/');
string str = items[2] + "/" + items[0] + "/" + items[1];

When you said globalization, I assume you want the change to be automatic according to current culture
You can setup culture (at Global.asax.cs I suggest)
System.Threading.Thread.CurrentThread.CurrentCulture = System.Threading.Thread.CurrentThread.CurrentUICulture = CultureInfo.GetCultureInfo("the culture you want to set"); //
you do not need to touch any datetime thing, it just happened when you output them.

One thing is not the other.
Not sure why you want to insist on the text entered being MM/dd/yyyy, or why you haven't used a date time picker to make sure it is a date.
But at the point you get the content of the textbox as a date, parse it based on globalisation, or a set of acceptable formats. Now it is a date, and assuming it's a date in the database, format is irrelevant until you come to populate the text box, with some content from the DB, inwhich case you use DateTime's ToString method witha globalisation parameter, usually CultureInfo.CurrentCulture, or if you've got away with it CultureInfo.InvariantCulture.
If it's a string in the DB, then this is the least of your problems.
They key point is if you use dates properly, format is only relevant for Parse, and ToString type methods.

i am using
IFormatProvider culture=new CultureInfo("en-GB",true);
sqlcommand cmd=new sqlcommand("query",con);
cmd.Parameters.AddWithValue("#date",DateTime.Parse(txtdate.Text.Trim(),culture,DateTimeStyles.NoCurrentDateDefault).Date);
for this to work the format property must be set to dd/MM/yyyy
and text box read only property must be false

How to make DateTime independent from the current culture?

I cam trying to convert a datetime to string and back, but making it so that it works for all cultures.
I basically have a Textbox (tbDateTime) and a label (lbDateTime). The label tells the user, in which format the software expects the input of tbDateTime. The input of the Textbox will be used for an MySQL command.
Currently it works like this:
lbDateTime.Text = "DD.MM.YYYY hh:mm:ss"; // I live in germany
DateTime date = Convert.ToDateTime(tbDateTime.Text);
String filter = date.ToString("yyyy-MM-dd HH:mm:ss");
Now my question:
Is it possible to determine the format-string for lbDateTime.Text based on the current culture?
Which format does the Convert.ToDateTime function uses?
I hope you can help me. I have actually no pc here to test different cultures, so I'm very afraid that I make something wrong.

Instead of using the Convert.ToDateTime method you can use the DateTime.Parse or DateTime.ParseExact methods. Both allow you to pass a culture that tells how you expect the date to be formatted.
The DateTime.ParseExact method also allows you to specify the format you expect, so you can parse more or less any format with this method.
Edit:
Regarding Convert.ToDateTime. The documentation says that the current culture is used when parsing: http://msdn.microsoft.com/en-us/library/xhz1w05e.aspx
The current culture can be found using the System.Threading.Thread.CurrentThread.CurrentCulture property.
Edit2:
Oh. You may also want to use DateTime.TryParse and DateTime.TryParseExact if you are unsure whether the given format is invalid.
Edit3:
Lots of edits here... I see that you want to determine the culture string that matches the date the user has entered. There is no general solution that is guaranteed to work here. Say for instance that the user has entered the date 01.02.11. There is no way to be certain if this date is in day.month.year or month.day.year or year.month.day and so on.
The best you can do is to have a list of expected input cultures and start with the most likely and try to parse the date using that. If that fails, you can try the second most likely and so on...
But this is really not recommended. Either give the user an expected format, or better, use a date input box that ensures that you receive the selected date in an appropriate format.

The Convert.ToDateTime method will call DateTime.Parse to parse the string, using the current culture (CultureInfo.Current).
You can specify a culture when parsing the string. Example:
DateTime data = DateTime.Parse(tbDateTime.Text, new CultureInfo("en-GB"));
You can use DateTime.ParseExact (or DateTime.TryParseExact) to parse the string using a custom date format. Example:
DateTime data = DateTime.ParseExact(tbDateTime.Text, "dd'.'MM'.'yyyy HH':'mm':'ss", CultureInfo.InvariantCulture);

Another solution :
// Specify the current language (used in the current system you are working on)
CultureInfo currentCulture = CultureInfo.GetCultureInfo(CultureInfo.CurrentCulture.ToString());
// Specify the language that we need
CultureInfo myLanguage = CultureInfo.GetCultureInfo("en-US");
// Adapt the DateTime here, we will use the current time for this example
DateTime currentDate = DateTime.Now;
// The date in the format that we need
string myDate = DateTime.Parse(currentDate.ToString(), currentCulture).ToString(myLanguage);