Server side validation for DATE format dd/mm/yyyy

DateTime.Parse(strinput);
            string[] arr = strinput.Split('/');
            string strNewDate = arr[1] + "/" + arr[0] + "/" + arr[2];

            string strRegex = @"^(?:(?:31(\/|-|\.)(?:0?[13578]|1[02]))\1|(?:(?:29|30)(\/|-|\.)(?:0?[1,3-9]|1[0-2])\2))(?:(?:1[6-9]|[2-9]\d)?\d{2})$|^(?:29(\/|-|\.)0?2\3(?:(?:(?:1[6-9]|[2-9]\d)?(?:0[48]|[2468][048]|[13579][26])|(?:(?:16|[2468][048]|[3579][26])00))))$|^(?:0?[1-9]|1\d|2[0-8])(\/|-|\.)(?:(?:0?[1-9])|(?:1[0-2]))\4(?:(?:1[6-9]|[2-9]\d)?\d{2})$"; // dd/mm/yyyy
            //@"^([0]\d|[1][0-2])\/([0-2]\d|[3][0-1])\/([2][01]|[1][6-9])\d{2}(\s([0-1]\d|[2][0-3])(\:[0-5]\d){1,2})?$"; // MM/dd/yyyy

            Regex re = new Regex(strRegex);

            if (re.IsMatch(strNewDate))
                return (true);
            else
                return (false);