how to update data on c# console application. alredy i have retrive data

using System;
using System.Data;
using System.Data.SqlClient;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace project
{
    class data
    {
        static void getdata()
        {

            SqlConnection con = new SqlConnection("Data Source=SANKALPA-PC;Initial Catalog=libray;Integrated Security=True");
            con.Open();
            DataSet ds = new DataSet();
            try
            {
                string sql = "select * from book1";
                SqlCommand cmd = new SqlCommand(sql, con);
                SqlDataReader dr = cmd.ExecuteReader();
                while (dr.Read())
                {
                    printrow(Convert.ToString(dr["bookid"]), Convert.ToString(dr["title"]), Convert.ToString(dr["author"]), Convert.ToString(dr["publisher"]), Convert.ToString(dr["price"]));

                }
             
                con.Close();
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);

            }
        }
    

        static void printline()
        {
            Console.WriteLine(new string('-', 80));
        }
        static void printrow(string bookid, string title, string author, string publisher, string price)
        {
            Console.WriteLine(string.Format("|{0}|{1}|{2}|{3}|{4}|",AlignCenter(bookid,17),AlignCenter(title,17),AlignCenter(author,17),AlignCenter(publisher,17),AlignCenter(price,17)));
        }
        static string AlignCenter(string text, int width)
        {

            if (string.IsNullOrEmpty(text))
            {
                return new string(' ', width);

            }

            else
            {

                //return text.PadRight(width - (width – text.Length) / 2).PadLeft(width);
                return text.PadRight(width - (width - text.Length) / 2).PadLeft(width);

            }

        }
   
   

        static void Main(string [] args)
        {
            printline();
            printrow("bookid","title","author","publisher","price");
            printline();
            getdata();
            Console.ReadKey();
        }

        
    }
}