Question

I’ve got DateTime variable and i want to convert it to string “DD.MM.YYYY”
Please note, the values must be separated by “dot” sign.

Of course I can do manual string composition. But I wonder if I can use DateTime.ToString()
to do required conversion.

Answer 1

Yes, you can:

string formatted = dt.ToString("dd'.'MM'.'yyyy");

Now in this case the quotes aren’t actually required, as custom date/time format strings don’t interpret dot in any special way. However, I like to make it explicit – if change ‘.’ for ‘:’ for example, then while it’s quoted it will stay with the explicit character, but unquoted it would be “the culture-specific time separator”. It wasn’t entirely obvious to me whether “.” would be interpreted as “the culture-specific decimal separator” or not, hence the quoting. You may feel that’s over the top, of course – it’s entirely your decision.

You may also want to specify the invariant culture, just to remove any other traces of doubt:

string formatted = dt.ToString("dd'.'MM'.'yyyy", CultureInfo.InvariantCulture);

(At that point the quotes around the dot become less relevant, as “.” is the decimal separator in the invariant culture anyway.)