Convert string of "dd/MM/yyyy" format into Datetime using C#?

You should use DateTime.ParseExact, to get the correct results

DateTime dt=DateTime.ParseExact("19/02/2017", "dd/MM/yyyy", CultureInfo.InvariantCulture);

Read more about Datetime.ParseExact 

Or You can use DateTime.TryParseExact , it is also same, code will be like this

DateTime dt;
if (DateTime.TryParseExact("19/02/2017", "dd/MM/yyyy", 
                            CultureInfo.InvariantCulture, 
                            DateTimeStyles.None,
    out dt))
{
    //date is valid, do something here
}

You can pass your date in the code below

string formattedDate = date.ToString("dd/MM/yyyy", CultureInfo.InvariantCulture)