Here is what you are looking for:
String sDate = DateTime.Now.ToString();
DateTime datevalue = (Convert.ToDateTime(sDate.ToString()));
String dy = datevalue.Day.ToString();
String mn = datevalue.Month.ToString();
String yy = datevalue.Year.ToString();
OR
Alternatively, you can use split function to split string date into day, month and year here.
Hope, it will helps you... Cheers. !!