Modify C# program to sort repeated item for point of sales

Question

Hi, is there anyone who can help me to modify a program regarding point of sales checkout system. Right now this program has the only the general feature and i need to to modify it to sort the number of repeated item. I have written a comment in purple next to the method. Thanks....! The source code is as below
 
using System;
using System.Collections.Generic;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Data.SqlClient;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
namespace PointofSales
{
public partial class FrmMain : Form
{
// database connection string for SQLServer 2005
private string dbConn = "Data Source=SE\\sqlexpress;Initial Catalog=PointOfSales;Trusted_Connection=True";
private string ReadCommand = "SELECT id, antenna_id, read_count, protocol_id FROM tag_id WHERE protocol_id='GEN2' set time_out=1000;";
private ReaderMode readermode = ReaderMode.Read;
// add a delegate & an event
public delegate void TCPDataUpdateHandler(object sender, TCPEventArgs e);
public event TCPDataUpdateHandler TCPDataUpdated;
private enum ReaderMode
{
Read,
Write
}
public FrmMain()
{
InitializeComponent();
InitApp();
// select thing magic reader
axInRFIDCtrl1.SelectThingMagic();
axInRFIDCtrl1.ReaderIPAddress = "10.0.0.101";
axInRFIDCtrl1.ReaderTCPPort = "8080";
}
private void exitToolStripMenuItem_Click(object sender, EventArgs e)
{
this.Close();
}
private void aboutToolStripMenuItem_Click(object sender, EventArgs e)
{
MessageBox.Show("RFID Point of Sales by Intensecomp Pte Ltd. Developed in Year 2009");
}
private void addNewProductToolStripMenuItem_Click(object sender, EventArgs e)
{
FrmAddProduct frm = new FrmAddProduct(dbConn);
if (frm.ShowDialog() == DialogResult.OK)
{
// process return value from dialog
}
}
// initialize application
private void InitApp()
{
LoadInventoryData(dbConn);
lstOrder.Clear();
lstOrder.Columns.Add("ID", 50);
lstOrder.Columns.Add("Description", 100);
lstOrder.Columns.Add("Price", 80);
lstOrder.Columns.Add("Quantity", 70);
btnAddOrder.Enabled = false;
btnRegister.Enabled = false;
}
// add item on list view
private void LoadInventoryData(string sqlConn)
{
// establish connection to SQLServer
System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection();
conn.ConnectionString = sqlConn;
// prepare sql statement
string sql = string.Empty;
sql = "select TagId, ProductName as 'Product Name', Description, UnitPrice As 'Price' from Tag, Product where ProductId = Product.Id";

SqlDataReader rdr = null;
try
{
// Open the connection
conn.Open();
SqlCommand cmd = new SqlCommand(sql, conn);
// get query results
rdr = cmd.ExecuteReader();
lstData.Clear();
for (int j = 0; j < rdr.FieldCount; j++)
{
lstData.Columns.Add(rdr.GetName(j), rdr.GetName(j).Length * 2 + 150);
}
// print the CustomerID of each record
int k = 1;
while (rdr.Read())
{
ListViewItem lst = new ListViewItem(rdr[0].ToString());
for (int i = 1; i < rdr.FieldCount; i++)
{
// if column is unit price, convert from int to decimal.
if (i == 3)
{
double money = Convert.ToDouble(rdr[i].ToString());
money = money / 100;
lst.SubItems.Add(money.ToString("$##.00"));
}
else
lst.SubItems.Add(rdr[i].ToString());
}
lstData.Items.Add(lst);
k++;
}
}
catch (Exception ex)
{
throw new Exception("Exception occur at AssetInfo.GetAll()-->" + ex.Message);
}
finally
{
// close the reader
if (rdr != null)
{
rdr.Close();
}
// Close the connection
if (conn != null)
{
conn.Close();
}
}
}
// add new order.
private void btnAddOrder_Click(object sender, EventArgs e)  //click on scan button to call this method to scan
{

for (int x = 0; x < 5; x++)
{
// read from RFID tag
string tagid = string.Empty;
// send data to Reader
axInRFIDCtrl1.TMagicSend(ReadCommand);
}
}
public string GetTagData(string tagid)
{
string result = string.Empty;
System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection();
conn.ConnectionString = dbConn;
SqlDataReader rdr = null;
try
{
// Open the connection
conn.Open();
// Pass the connection to a command object
string sql = string.Empty;
sql = "select Tag.TagID, ProductName as 'Product Name', UnitPrice As Price from Tag,Product where ProductId = Product.Id and Tag.TagID = '" + tagid + "'";
SqlCommand cmd = new SqlCommand(sql, conn);
// get query results
rdr = cmd.ExecuteReader();
while (rdr.Read())
{
result = rdr[0].ToString() + "|" + rdr[1].ToString() + "|" + rdr[2].ToString();
}
}
catch (Exception ex)
{
throw new Exception("Exception occur at GetEventList()-->" + ex.Message);
}
finally
{
// close the reader
if (rdr != null)
{
rdr.Close();
}
// Close the connection
if (conn != null)
{
conn.Close();
}
}
return result;
}
public int GetProductId(string tagid)
{
int result = 0;
System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection();
conn.ConnectionString = dbConn;
SqlDataReader rdr = null;
try
{
// Open the connection
conn.Open();
// Pass the connection to a command object
string sql = string.Empty;
sql = "select ProductId from Tag where Tag.TagID = '" + tagid + "'";
SqlCommand cmd = new SqlCommand(sql, conn);
// get query results
rdr = cmd.ExecuteReader();
while (rdr.Read())
{
result = Convert.ToInt32(rdr[0]);
}
}
catch (Exception ex)
{
throw new Exception("Exception occur at GetEventList()-->" + ex.Message);
}
finally
{
// close the reader
if (rdr != null)
{
rdr.Close();
}
// Close the connection
if (conn != null)
{
conn.Close();
}
}
return result;
}
public int GetLastOrderId()
{
int result = 0;
System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection();
conn.ConnectionString = dbConn;
SqlDataReader rdr = null;
try
{
// Open the connection
conn.Open();
// Pass the connection to a command object
string sql = string.Empty;
sql = "select Max(Id) from OrderInfo";
SqlCommand cmd = new SqlCommand(sql, conn);
// get query results
rdr = cmd.ExecuteReader();
while (rdr.Read())
{
result = Convert.ToInt32(rdr[0]);
}
}
catch (Exception ex)
{
throw new Exception("Exception occur at GetEventList()-->" + ex.Message);
}
finally
{
// close the reader
if (rdr != null)
{
rdr.Close();
}
// Close the connection
if (conn != null)
{
conn.Close();
}
}
return result;
}
// add new product item to the inventory
private void btnRegister_Click(object sender, EventArgs e)
{
// select a product and assign to RFID tag
FrmRegister frm = new FrmRegister(this, dbConn, axInRFIDCtrl1);
if (frm.ShowDialog() == DialogResult.OK)
{
LoadInventoryData(dbConn);
}
}
private void btnClear_Click(object sender, EventArgs e)
{
lstOrder.Items.Clear();
}
private void startReaderToolStripMenuItem_Click(object sender, EventArgs e)
{
if (axInRFIDCtrl1.TMagicConnect() > 0)
{
//axInRFIDCtrl1.ISOSet15693();
MessageBox.Show("RFID Reader ready for operation");
btnAddOrder.Enabled = true;
btnRegister.Enabled = true;
}
else
MessageBox.Show("RFID Reader not found");
}
private void stopReaderToolStripMenuItem_Click(object sender, EventArgs e)
{
axInRFIDCtrl1.TMagicDisconnect();
MessageBox.Show("RFID Reader has been stopped");
btnAddOrder.Enabled = false;
btnRegister.Enabled = false;
}
private void btnRefresh_Click(object sender, EventArgs e)
{
LoadInventoryData(dbConn);
}
private void btnPay_Click(object sender, EventArgs e)
{
// nothing in the list, do not process
if (lstOrder.Items.Count <= 0)
return;
// calculate payment summary
int tprice = 0;
for(int j=0; j< lstOrder.Items.Count; j++)
{
tprice += Convert.ToInt32((Convert.ToDouble(lstOrder.Items[j].SubItems[2].Text.Replace("$", "")) * 100));
}
frmPayment frm = new frmPayment(tprice);
if (frm.ShowDialog() == DialogResult.OK)
{
// process the order, create order first
int orderid = CreateOrder(dbConn);
if (orderid > 0)
{
orderid = GetLastOrderId();
for (int i = 0; i < lstOrder.Items.Count; i++)
{
int price = 0;
string tagid = lstOrder.Items[i].Text;
price = Convert.ToInt32((Convert.ToDouble(lstOrder.Items[i].SubItems[2].Text.Replace("$", "")) * 100));
int productid = 0;
productid = GetProductId(tagid);
int oid = InsertOrderDetails(dbConn, orderid, tagid, price, productid);
if (oid > 0)
{
// save completed, remove item from inventory
RemoveInventory(dbConn, tagid);
}
}
lstOrder.Items.Clear();
// update inventory record
LoadInventoryData(dbConn);
}
}
}
private int CreateOrder(string sqlconn)
{
int result = 0;
// setup connection
System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection();
conn.ConnectionString = sqlconn;
try
{
// Open the connection
conn.Open();
// Pass the connection to a command object
string sql = string.Empty;
sql = "INSERT ORDERINFO (fPaid) VALUES (1)";
SqlCommand cmd = new SqlCommand(sql, conn);
// execute cmd with non query
result = cmd.ExecuteNonQuery();

}
catch (Exception ex)
{
throw new Exception("Exception occur at GetEventList()-->" + ex.Message);
}
finally
{
// Close the connection
if (conn != null)
0 {
conn.Close();
}
}
return result;
}
private int InsertOrderDetails(string sqlconn, int orderid, string tagid, int price, int productid)
{
int result = 0;
System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection();
conn.ConnectionString = sqlconn;
try
{
// Open the connection
conn.Open();
// Pass the connection to a command object
string sql = string.Empty;
sql = "INSERT ORDERDETAILS (OrderId, TagId, UnitPrice, ProductId) VALUES ("+ orderid.ToString() + ",'" + tagid + "'," + price.ToString() + "," + productid + ")";
SqlCommand cmd = new SqlCommand(sql, conn);
result = cmd.ExecuteNonQuery();
}
catch (Exception ex)
{
throw new Exception("Exception occur at GetEventList()-->" + ex.Message);
}
finally
{
// Close the connection
if (conn != null)
{
conn.Close();
}
}
return result;
}
private int RemoveInventory(string sqlconn, string tagid)
{
int result = 0;
System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection();
conn.ConnectionString = sqlconn;
try
{
// Open the connection
conn.Open();
// Pass the connection to a command object
string sql = string.Empty;
sql = "DELETE FROM Tag where TagId = '" + tagid + "'";
SqlCommand cmd = new SqlCommand(sql, conn);
result = cmd.ExecuteNonQuery();
}
catch (Exception ex)
{
throw new Exception("Exception occur at GetEventList()-->" + ex.Message);
}
finally
{
// Close the connection
if (conn != null)
{
conn.Close();
}
}
return result;
}
private void viewOrderHistoryToolStripMenuItem_Click(object sender, EventArgs e)
{
frmViewOrder frm = new frmViewOrder(dbConn);
if (frm.ShowDialog() == DialogResult.OK)
{
}
}
private void viewProductListToolStripMenuItem_Click(object sender, EventArgs e)
{
frmViewProduct frm = new frmViewProduct(dbConn);
if (frm.ShowDialog() == DialogResult.OK)
{
}
}
// reply from the reader  this should be the part where i need to write a method to sort repeated item.
private void axInRFIDCtrl1_DataReceived(object sender, AxINRFIDCTRLLib._DInRFIDCtrlEvents_DataReceivedEvent e)
{
string msg = string.Empty;
try
{
// data received from reader
// e
msg = e.data;
// process
msg = msg.TrimEnd('\n');
msg = msg.TrimStart('\n');
/*
if (msg.Length <= 0)
{
UpdateLabel(lblLog, "No tag available", UpdateType.New);
if (readermode == ReaderMode.Write)
{
Thread.Sleep(1000);
ReadTag(writeantenna);
}
else
return;
}
*/
// update text box
//UpdateTextBox(tbxRawData, System.DateTime.Now.ToString() + " " + msg + "\r\n", UpdateType.Add);
//WriteProcessLog(msg, true);
int readcount = 0;
string[] tag = msg.Split('\n');
switch (readermode)
{
case ReaderMode.Read:
if (msg.Length > 0)
{
if (msg.IndexOf("Error") <= 0)
{
for (int i = 0; i < tag.Length; i++)
{
string[] data = tag[i].Split('|');
readcount = Convert.ToInt32(data[2]);
string result = string.Empty;
string tagid = data[0].Remove(data[0].Length - 4, 4);
// get data from database by tag id
result = GetTagData(tagid);
if (result != "")
{
string[] res = result.Split('|');
int count = 0;
/*
// search for tagid if already in the list, then ignore
for (int j = 0; j < lstOrder.Items.Count; j++)
{
if (lstOrder.Items[j].Text == tagid)
{
count++;
break;
}
}
if (count <= 0)
{
// convert price from int to decimal
res[2] = (Convert.ToDouble(res[2]) / 100).ToString("$##.00");
ListViewItem lst = new ListViewItem(res);
lstOrder.Items.Add(lst);
}
*/
res[2] = (Convert.ToDouble(res[2]) / 100).ToString("$##.00");
// update list box
// consolidate the tags scanned
ListViewItem lst = new ListViewItem(res);
UpdateListView(lstOrder, lst);
}
else
{
//MessageBox.Show("Error getting tag data. Tag may not exist in inventory");
// instance the event args and pass it each value
TCPEventArgs args = new TCPEventArgs(tagid);
if (TCPDataUpdated != null)
TCPDataUpdated(new object(), args);
}
}
// update here for qty
}
else
{
//UpdateLabel(lblLog, msg, UpdateType.New);
}
//UpdateLabel(lblLog, "Read completed", UpdateType.New);
}
break;
case ReaderMode.Write:
/*
if (msg.Length > 0)
{
if (tag.Length == 1)
{
if (msg.IndexOf("Error") <= 0)
{
string[] data = tag[0].Split('|');
if (completecount >= writecount)
{
//update list view
ListViewItem item = new ListViewItem(msg);
UpdateListView(lstData, item);
UpdateLabel(lblLog, "Write operation completed.", UpdateType.New);
UpdateButtonText(btnWrite, "Write", UpdateType.New);
}
else
{
// check for previous tag
string prevtagid = String.Format("0x{0:X24}", prewriteID);
string comparetag = data[0].Remove(data[0].Length - 4, 4);
WriteProcessLog(prevtagid + " " + comparetag, true);
if (comparetag == prevtagid)
{
//update list view
ListViewItem item = new ListViewItem(msg);
UpdateListView(lstData, item);
UpdateLabel(lblLog, "Put a new tag to retry. Writing ID: " + writeID.ToString(), UpdateType.New);
Thread.Sleep(2000);
ReadTag(writeantenna);
}
else
{
string tagid = String.Format("0x{0:X24}", writeID);
prewriteID = writeID; // store previous write id
InsertTagInfo(tagid);
WriteTag(writeID, writeantenna);
writeID++;
completecount++;
UpdateLabel(lblLog, "Write " + tagid + " successful", UpdateType.New);
Thread.Sleep(500);
}
}
}
else
{
UpdateLabel(lblLog, msg, UpdateType.New);
{
Thread.Sleep(1000);
ReadTag(writeantenna);
}
}
}
else
{
UpdateLabel(lblLog, "Too many tags detected", UpdateType.New);
WriteProcessLog("Too mang tags - " + msg, true);
Thread.Sleep(1000);
ReadTag(writeantenna);
}
}
else
{
UpdateLabel(lblLog, "No reply from reader", UpdateType.New);
Thread.Sleep(1000);
ReadTag(writeantenna);
}
*/
break;
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, ex.Source);
}
 
}
private void FrmMain_FormClosing(object sender, FormClosingEventArgs e)
{
axInRFIDCtrl1.TMagicDisconnect();
}
// this function updates listview item if available, add new item if not available.
private void UpdateListView(ListView control, ListViewItem item)
{
if (control.InvokeRequired)
{
MethodInvoker invoker = new MethodInvoker(delegate()
{
if (control.Items.Count > 0)
{
ListViewItem foundItem = control.FindItemWithText(item.Text, true, 0, true);
if (foundItem == null)
{
control.Items.Add(item);
}
else
{
/*
// update read count, subitem no 2
if (foundItem.SubItems.Count >= 3 && item.SubItems.Count >= 3)
{
foundItem.SubItems[2].Text = Convert.ToString(Convert.ToInt32(foundItem.SubItems[2].Text) + Convert.ToInt32(item.SubItems[2].Text));
}
*/
}
}
else
control.Items.Add(item);
});
Invoke(invoker);
}
else
{
if (control.Items.Count > 0)
{
ListViewItem foundItem = control.FindItemWithText(item.Text, true, 0, true);
if (foundItem == null)
{
control.Items.Add(item);
}
else
{
/*
// update read count, subitem no 2
foundItem.SubItems[2].Text = Convert.ToString(Convert.ToInt32(foundItem.SubItems[2].Text) + Convert.ToInt32(item.SubItems[2].Text));
*/
}
}
else
control.Items.Add(item);
}
}
private void RemoveItemListView(ListView control, string item)
{
if (control.InvokeRequired)
{
MethodInvoker invoker = new MethodInvoker(delegate()
{
// remove client from list view
for (int i = 0; i < control.Items.Count; i++)
{
ListViewItem it = control.Items[i];
if (it.SubItems[0].Text == item)
{
control.Items.RemoveAt(i);
break;
}
}
});
Invoke(invoker);
}
else
{
// remove client from list view
for (int i = 0; i < control.Items.Count; i++)
{
ListViewItem it = control.Items[i];
if (it.SubItems[0].Text == item)
{
control.Items.RemoveAt(i);
break;
}
}
}
}
}
public class TCPEventArgs : System.EventArgs
{
private string mMachineId = string.Empty;
private string mPacket = string.Empty;
private string mCommand = string.Empty;
public TCPEventArgs(string packet)
{
mPacket = packet;
}
public string MachineId
{
get { return mMachineId; }
}
public string Packet
{
get { return mPacket; }
}
public string CommandCode
{
get { return mCommand; }
}
}
}