A DateTime doesn't
have a format - it is stored as a number of milliseconds since an arbitrary point in time, so all it has is a number!
It only acquires a format when it is prepared for presentation to a user bymenas of the ToString method, either explicitly via a call:
string myDate = dt.ToString();
Or implicitly:
Console.WriteLine(dt);
Or
string myDate = "The date is " + dt;
When the conversion to a string is done, the culture in effect on the PC doing the conversion controls how the resulting string is formatted.
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You can override the default formatting by specifying the exact output format you want - see here:
Formatting a DateTime for display - format string description[
^]
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