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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.TryParse issue, may relate to Globalization Setting in IIS

Basically,I am reading excel file where one of that columns has date format like : dd/MM/yyyy eg: 11/04/2016
When I am using DateTime.TryParse() to parse that string into datetime method TryParse() treated first numbers like month (number 11 in example above). However the same code running on the other computers will take the second number (04 in example above) as the month.
So my question is why there is a difference between them, what actually decide the behavior of TryParse method?

I think the main difference is in IFormatProvider (hard to say if I can't check some settings in target system), but I usually use other method to get proper DateTime object:
DateTime someDate = DateTime.ParseExact(myStringDate, "dd/MM/yyyy", System.Globalization.CultureInfo.InvariantCulture);
It always gives me what I want no matter how client environment is configured.
Hope this helps. :)

From DateTime.TryParse(String, DateTime) documentation:
Because the DateTime.TryParse(String, DateTime) method tries to parse
the string representation of a date and time using the formatting
rules of the current culture, trying to parse a particular string
across different cultures can either fail or return different results.
If a specific date and time format will be parsed across different
locales, use the
DateTime.TryParse(String, IFormatProvider, DateTimeStyles, DateTime)
method or one of the overloads of the TryParseExact method and provide
a format specifier.
That means your computers have different culture settings which is pointed in CurrentCulture property.
Looks like one computer's current culture have dd/MM/yyyy and the other computer's current culture have MM/dd/yyyy as a standard date and time format.
Since you are sure your values are always in dd/MM/yyyy format, I would use DateTime.ParseExact instead of Datetime.TryParse or DateTime.TryParseExact methods like;
var dt = DateTime.ParseExact(yourColumnValue, "dd/MM/yyyy", CultureInfo.InvariantCulture);
Or you can sets all computers current culture to like the first computer but remember, CultureInfo data is not a stable data that might be change in future with a windows update, .NET Framework version or OS version.

Flexible DateTime parsing on multi culture web application

I have an ASP.NET web application which is multi culture meaning I have en-us, en-ca, fr-ca, etc.
My problem is when I am trying to Parse a date 1/22/2014 using DateTime.Parse and I am using en-us, it will work because the ShortDatePattern of en-us is M/dd/yyyy but if the user is en-ca, the ShortDatePattern is dd/MM/yyyy.
How can I parse the dates considering different cultures? I have tried the following codes:
DateTime.Parse(date);
DateTime.ParseExact(date, ShortDatePattern, Culture);
DateTime.TryParseExact(date, ShortDatePattern, Culture, DateTimeStyles.None, out date);
But still no luck for me.
EDIT
DateTime.Parse throws me an exception, string is not a valid datetime. Same with the DateTime.ParseExact. DateTime.TryParseExact give me a date of 1/1/0001.

If you're absolutely sure of the user's culture - and that they'll actually use that - you could use:
// I assume that Culture is a valid reference to a CultureInfo...
DateTime date = DateTime.Parse(date, Culture);
However, I'd strongly consider providing a calendar control or separate year/text-month/day fields on the page (with validation) so that what you post back to ASP.NET can be a machine-readable, culture-neutral date format, e.g. yyyy-MM-dd. Basically, turn the culture-sensitive representation into a culture-neutral representation as early as you can.

If the user can choose multiple languages within your application, I would think it would be easier to cater for the multiple language choices.
Here is what I did sometime ago:
DateTime dateValue = DateTime.Parse(dateVar.ToString());
string currentCulture = XmlLanguage.GetLanguage(CultureInfo.CurrentCulture.IeftLanguageTag).ToString();
CultureInfo culture = new CultureInfo(currentCulture);
Console.WriteLine(dateValue.ToString("d", culture));
DateVar being the date value that you want to convert to new culture.
The above code makes use of the System.Windows.Markup namespace
Just change Console.WriteLine your preferred output display.

Convert.DateTime throws error: String was not recognized as a valid DateTime for "06-13-2012"

I am inserting a date into my database, the value which comes from:
s.theDate = Convert.ToDateTime("06-13-2012");
and I get the error, "String was not recognized as a valid DateTime". How do I resolve this?

Try this:
DateTime.ParseExact("06-13-2012", "MM-dd-yyyy", System.Globalization.CultureInfo.InvariantCulture)

s.theDate = DateTime.ParseExact("06-13-2012", "MM-dd-yyyy", System.Globalization.CultureInfo.InvariantCulture)

Looking at the behaviour of ToString on a DateTime type using an InvariantCulture, this:
new DateTime(2012, 6, 13).ToString(CultureInfo.InvariantCulture)
results in:
06/13/2012 00:00:00
So, conversely, one can assume that parsing the date with an invariant culture works Ok:
Convert.ToDateTime("06-13-2012", CultureInfo.InvariantCulture)
... and it does.
That being said, assuming date/time formats is a little dangerous. I'd say you want formats to be culture-specific when the UI is considered. Otherwise, you would want formats to be culture-agnostic. Although Microsoft have adopted MM/dd/yyyy as a culture-agnostic format, it's an ambiguous format which isn't something that I would want to build a large system on.

Just use ParseExact as already suggested or populate Convert.ToDateTime with the second parameter:
Convert.ToDateTime("06-13-2012", new DateTimeFormatInfo{FullDateTimePattern = "MM-dd-yyyy"});

There is a global standard called ISO 8601 that you may (imo should) use. Using this standard, this is what you will end up with.
Convert.ToDateTime("2012-06-03");

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);