Question

I receive Date and time from CSV file

The received Date format is  YYYYMMDD (string) (there is no ":" ,"-","/" to 
separate  Year month and date).

The received time format is HH:MM (24 Hour clock).

I have to validate both so that (example) (i) 000011990 could be invalidated for date (ii) 77:90 could be
invalidated for time.

The question is ,

Regular expression is the right candidate for do so (or) is there any other way to achieve
it?

Answer 1

You’re looking for DateTime.TryParseExact:

string source = ...;
DateTime date;
if (!DateTime.TryParseExact(source, 
                            "yyyyMMdd", 
                            CultureInfo.InvariantCulture, 
                            DateTimeStyles.None, 
                            out date)) {
    //Error!
}

You can use the same code to validate times, with the format string "HH:mm".