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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

string to dateTime convention changes the format of the string

My code is like this
DateTime dt = new DateTime();
dt= DateTime.ParseExact("14/09/2017", "dd/MM/yyyy", CultureInfo.InvariantCulture);
I am expecting dt to have a format of dd/MM/yyyy but the output I am getting is in MM/dd/yyyy format.
This is the correct out put I am getting 9/14/2017 12:00:00 AM.
Can anyone please point out what I am doing wrong here?

if you expect the format "dd/MM/yyyy" you need to specify it when displaying the DateTime. To do so you can use this overload of the ToString method:
dt.ToString("dd/MM/yyyy");
A DateTime on it's own has no format. Only the string representation of it has one.
EDIT:
Important remark by Tim Schmelter:
/ is a custom format specifier which replaces all occurences with the local date-separator. You either have to esacape them by embedding them within ' or use CultureInfo.InvariantCulture as second parameter. Read this post
That means either use this:
string str_rep = dt.ToString("dd'/'MM'/'yyyy");
or:
string str_rep = dt.ToString("dd/MM/yyyy", CultureInfo.InvariantCulture);

Your dt is a DateTime, not a string. Format concept only applies when you get their textual (aka string) representation. What you saw is probably what debbuger/ide shows you as a textual representation.
If you get a specific format of your dt, then you can use .ToString() method with dd/MM/yyyy format and a proper culture like InvariantCulture.
string myFormat = dt.ToString("dd/MM/yyyy", CultureInfo.InvariantCulture);
For beginners, it is really important to understand the difference between what is a DateTime and what is their string representation.

If DateTime.ToString() is resulting in an unexpected format, the likely case is that the current culture isn't being set. By default, the date format used is taken from the host machine. However, you can either specify it directly by setting the thread's CurrentCulture for the culture code you need, or you can set it in your application's configuration file. E.g., a web application's web.config can have a globalization section, like so;
<globalization culture="en-GB" uiCulture="en-GB" />
Alternatively, as already specified, you can set the format explicitly via a custom format string .ToString("dd/MM/yyyy").

Datetime format is miss matching in c# when hosting

I had a situation that locally working but not in hosting (godaddy.com)
DateTime date = DateTime.Parse(TextBoxSelectedDate.Text.Trim());
string d = date.ToString("yyyy-MM-dd");//localhost out put 2013-10-13
DateTime.Parse(d);
but when I host is giving this exception
System.FormatException: String was not recognized as a valid DateTime.
Why is this
Thanks

Your hoster might be using a different language / region setting than you. Try calling Parse with a specific culture object:
DateTime.Parse("2013-10-13", CultureInfo.GetCultureInfo("the name of your culture, en-US for example"))
You can find a list of culture names here:
http://msdn.microsoft.com/en-us/goglobal/bb896001.aspx
You can also use CultureInfo.InvariantCulture

You use a format string when you go from DateTime to string. Use the same format string when you go in the opposite direction:
DateTime.ParseExact(d, "yyyy-MM-dd", null)
If you want to be absolutely sure the current culture of your thread doesn't mess things up, you can use the invariant culture:
DateTime.ParseExact(d, "yyyy-MM-dd", CultureInfo.InvariantCulture)

Getting system date in the correct local format?

Is there any way I can retrieve the phones system date format, eg: dd/MM/yyyy or MM/dd/yyyy ?

You can just use ToShortDateString().
The string returned by the ToShortDateString method is culture-sensitive. It reflects the pattern defined by the current culture's DateTimeFormatInfo object.
DateTime.Now.ToShortDateString();
According to the documentation (in link) it will display the date in the current date format.
For the actual format
CultureInfo.CurrentCulture.DateTimeFormat;

Does it work?
var formattedddMMyyyy = DateTime.Now.ToString("dd/MM/yyyy", CultureInfo.InvariantCulture);
var formattedMMddyyyy = DateTime.Now.ToString("MM/dd/yyyy", CultureInfo.InvariantCulture);

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);