OleDbConnection Base3 = new OleDbConnection
               (@"Provider= Microsoft.JET.OLEDB.4.0;Data Source=C:\Users\MaKsi\Desktop\Диплом\baza.mdb");
            Base3.Open();
            OleDbDataAdapter Adapter3 = new OleDbDataAdapter
                ("UPDATE Продукты SET Наименование = \"" + textBox4.Text + "\", Количество = \"" + textBox5.Text + "\", Дата = \"" + dateTimePicker2.Value.ToString("dd.MM.yyyy") + "\" WHERE Код = " + textBox3.Text + "", Base3);
            DataTable Table3 = new DataTable();
            Adapter3.Fill(Table3);
            Base3.Close();