c# dataset data adapter

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace DataAdapterDemo
{
    public partial class Form1 : Form
    {
        InventoryDB DB;
        public Form1()
        {
            InitializeComponent();

            //instantiate the data object
            DB = new InventoryDB();

            //bind the supplier table to the grid
            uxSuppliers.DataSource = DB.SupplierTable;
        }

        private void saveToolStripMenuItem_Click(object sender, EventArgs e)
        {
            DB.SaveChanges();
        }
    }
}

--------------------------------------------------------------------

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using System.Data;

using System.Data.SqlClient;

namespace DataAdapterDemo

{

    public class InventoryDB

    {

        private DataSet DB = new DataSet("Inventory");

        private SqlDataAdapter SupplierAdapter { get; set; }

        private string connectionString = 

            "server=localhost;database=Inventory;user id=sa;password=SQLPassword";

        public DataTable SupplierTable

        {

            get

            {

                return DB.Tables["Supplier"];

            }

        }

        public InventoryDB()

        {

            PopulateSupplierTable();

        }

        private void PopulateSupplierTable()

        {

            //instantiate the supplier adapter

            SupplierAdapter = 

                new SqlDataAdapter("SELECT * FROM Supplier", connectionString);

            //build the commands

            SqlCommandBuilder cb = new SqlCommandBuilder(SupplierAdapter);

            SupplierAdapter.InsertCommand = cb.GetInsertCommand();

            SupplierAdapter.UpdateCommand = cb.GetUpdateCommand();

            SupplierAdapter.DeleteCommand = cb.GetDeleteCommand();

            //fill the dataset

            SupplierAdapter.FillSchema(DB, SchemaType.Source, "Supplier");

            SupplierAdapter.Fill(DB, "Supplier");

        }

        public void SaveChanges()

        {

            SupplierAdapter.Update(DB.Tables["Supplier"]);

        }

    }

}