public string s ="Data Source=.;Initial Catalog=chaoshi;Integrated Security=True";
        private void CS() {
            if(listView1.Items.Count>0){
                listView1.Items.Clear();

            }
            StringBuilder sb = new StringBuilder();
            sb.AppendLine("SELECT [Name],[Type],[Number],[Price] FROM [chaoshi].[dbo].[shangpin]");
            sb.AppendFormat("WHERE [Type] LIKE '{0}'", this.textBox1.Text.Trim());
            MySchool.DBHelper a = new MySchool.DBHelper();
            try
            {
                SqlCommand command = new SqlCommand(sb.ToString(), a.Connection);
                a.OpenConnection();
                SqlDataReader reader = command.ExecuteReader();
                if (!reader.HasRows)
                {
                    MessageBox.Show("沒有記錄", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                }
                else
                {
                    while (reader.Read())
                    {
                        string name = reader["Name"].ToString();
                        string type = reader["Type"].ToString();
                        string number = reader["Number"].ToString();
                        string price = reader["Price"].ToString();
                        ListViewItem item = new ListViewItem(name);
                        item.SubItems.Add(type);
                        item.SubItems.Add(number);
                        item.SubItems.Add(price);
                        listView1.Items.Add(item);

                    }

                    reader.Close();

                }
            }
            catch (Exception e)
            {

                MessageBox.Show(e.Message, "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
            finally {
                a.CloseConnection();
            }
        }

        private void textBox1_TextChanged(object sender, EventArgs e)
        {
            
        }

        private void button1_Click(object sender, EventArgs e)
        {CS();

        }