Sending items to database and making a receipt in VB.NET - vb.net

Question

We have another IT project, and this time it's on VB.NET, it's actually going pretty good compared to the one we did on Java. So it's still a POS System, and I have six functions of the POS (for admins, and 4 for employees). Right now I'm almost done with the Cash Register function. I have a problem, though. The menu items are in buttons, and once you click a button, it appears in three listboxes (one for item name, quantity and price), and once a button is clicked more than once, it looks for the string with its name and updates the price and quantity. A keypad is adjacent to the buttons, for the input of the customer's payment. Once btnTransact is clicked, it checks for equality of the total amount and the amount paid. So it goes through if else statements and once everything is niff and dandy it shows that the transaction is completed in a message box.
I need the items in the listboxes to appear in either a form or a message box (if that's possible), but I don't know how. Also, I need the listbox items to be sent to a database, tbl_Invoice with columns "Invoice Number (autonumber)", "Invoice Date (there's a realtime clock in my POS)", "Product Code (in tbl_Products, each item has a specific item code", "Quantity", "Unit Price", "Employee ID (I have a log-in as well, and I need to get the Employee ID based on the logged-in user from tbl_Employees)". I will provide appendices.
Also, I have partially added a DisplayDeceipt sub just in case.
I'm sorry if I do not know a lot about VB.NET, only basic functions are being taught to us, and what they're asking from us is waaaay beyond basic. Your help is greatly appreciated. Thank you]1
Imports System.Data.OleDb
Public Class frmCR
Dim intTotal, intPlace As Integer
Dim quantCCS, quantSalad, quantKare, quantGarlic, quantAdobo, quantMushroom, quantAsul, quantDilaw, quantBasket, quantIslands As Integer
Private Sub btn1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn1.Click
txtPaid.Text += btn1.Text
End Sub
Private Sub btn2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn2.Click
txtPaid.Text += btn2.Text
End Sub
Private Sub btn3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn3.Click
txtPaid.Text += btn3.Text
End Sub
Private Sub btn4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn4.Click
txtPaid.Text += btn4.Text
End Sub
Private Sub btn5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn5.Click
txtPaid.Text += btn5.Text
End Sub
Private Sub btn6_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn6.Click
txtPaid.Text += btn6.Text
End Sub
Private Sub btn7_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn7.Click
txtPaid.Text += btn7.Text
End Sub
Private Sub btn8_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn8.Click
txtPaid.Text += btn8.Text
End Sub
Private Sub btn9_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn9.Click
txtPaid.Text += btn9.Text
End Sub
Private Sub btn0_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btn0.Click
txtPaid.Text += btn0.Text
End Sub
Private Sub btnDeci_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDeci.Click
txtPaid.Text += btnDeci.Text
End Sub
Private Sub btnClear_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnClear.Click
txtPaid.Clear()
End Sub
Private Sub btnCCS_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCCS.Click
quantCCS += 1
If quantCCS = 1 Then
lstItems.Items.Add("CAESALAD")
lstQuant.Items.Add(quantCCS)
lstPrice.Items.Add("160")
Else
intPlace = lstItems.FindStringExact("CAESALAD")
lstQuant.Items(intPlace) = (quantCCS)
lstPrice.Items(intPlace) += 160
End If
intTotal += 160
lblTotal.Text = intTotal
End Sub
Private Sub tmrCR_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles tmrCR.Tick
lblTime.Text = Format(Now, "MM-dd-yyyy hh:mm:ss")
End Sub
Private Sub frmCR_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
tmrCR.Enabled = True
End Sub
Private Sub btnSalad_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSalad.Click
quantSalad += 1
If quantSalad = 1 Then
lstItems.Items.Add("BBFSALAD")
lstQuant.Items.Add(quantSalad)
lstPrice.Items.Add("160")
Else
intPlace = lstItems.FindStringExact("BBFSALAD")
lstQuant.Items(intPlace) = (quantSalad)
lstPrice.Items(intPlace) += 160
End If
intTotal += 160
lblTotal.Text = intTotal
End Sub
Private Sub btnKare_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnKare.Click
quantKare += 1
If quantKare = 1 Then
lstItems.Items.Add("KAREKARE")
lstQuant.Items.Add(quantKare)
lstPrice.Items.Add("210")
Else
intPlace = lstItems.FindStringExact("KAREKARE")
lstQuant.Items(intPlace) = (quantKare)
lstPrice.Items(intPlace) += 210
End If
intTotal += 210
lblTotal.Text = intTotal
End Sub
Private Sub btnGarlic_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnGarlic.Click
quantGarlic += 1
If quantGarlic = 1 Then
lstItems.Items.Add("TAPAO")
lstQuant.Items.Add(quantGarlic)
lstPrice.Items.Add("180")
Else
intPlace = lstItems.FindStringExact("TAPAO")
lstQuant.Items(intPlace) = (quantGarlic)
lstPrice.Items(intPlace) += 180
End If
intTotal += 180
lblTotal.Text = intTotal
End Sub
Private Sub btnAdobo_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAdobo.Click
quantAdobo += 1
If quantAdobo = 1 Then
lstItems.Items.Add("ADOBODILAW")
lstQuant.Items.Add(quantAdobo)
lstPrice.Items.Add("145")
Else
intPlace = lstItems.FindStringExact("ADOBODILAW")
lstQuant.Items(intPlace) = (quantAdobo)
lstPrice.Items(intPlace) += 145
End If
intTotal += 145
lblTotal.Text = intTotal
End Sub
Private Sub btnMushroom_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnMushroom.Click
quantMushroom += 1
If quantMushroom = 1 Then
lstItems.Items.Add("MUSHCHICKEN")
lstQuant.Items.Add(quantMushroom)
lstPrice.Items.Add("160")
Else
intPlace = lstItems.FindStringExact("MUSHCHICKEN")
lstQuant.Items(intPlace) = (quantMushroom)
lstPrice.Items(intPlace) += 160
End If
intTotal += 160
lblTotal.Text = intTotal
End Sub
Private Sub btnAsul_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAsul.Click
quantAsul += 1
If quantAsul = 1 Then
lstItems.Items.Add("KNGASUL")
lstQuant.Items.Add(quantAsul)
lstPrice.Items.Add("35")
Else
intPlace = lstItems.FindStringExact("KNGASUL")
lstQuant.Items(intPlace) = (quantAsul)
lstPrice.Items(intPlace) += 35
End If
intTotal += 35
lblTotal.Text = intTotal
End Sub
Private Sub btnDilaw_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDilaw.Click
quantDilaw += 1
If quantDilaw = 1 Then
lstItems.Items.Add("KNGDILAW")
lstQuant.Items.Add(quantDilaw)
lstPrice.Items.Add("35")
Else
intPlace = lstItems.FindStringExact("KNGDILAW")
lstQuant.Items(intPlace) = (quantAsul)
lstPrice.Items(intPlace) += 35
End If
intTotal += 35
lblTotal.Text = intTotal
End Sub
Private Sub btnBasket_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnBasket.Click
quantBasket += 1
If quantBasket = 1 Then
lstItems.Items.Add("ICECRMBASKET")
lstQuant.Items.Add(quantBasket)
lstPrice.Items.Add("110")
Else
intPlace = lstItems.FindStringExact("ICECRMBASKET")
lstQuant.Items(intPlace) = (quantAsul)
lstPrice.Items(intPlace) += 110
End If
intTotal += 110
lblTotal.Text = intTotal
End Sub
Private Sub btnIslands_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnIslands.Click
quantIslands += 1
If quantIslands = 1 Then
lstItems.Items.Add("TSOKOISLAND")
lstQuant.Items.Add(quantIslands)
lstPrice.Items.Add("180")
Else
intPlace = lstItems.FindStringExact("TSOKOISLAND")
lstQuant.Items(intPlace) = (quantIslands)
lstPrice.Items(intPlace) += 180
End If
intTotal += 180
lblTotal.Text = intTotal
End Sub
Private Sub btnTransact_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnTransact.Click
Dim intAmount, intPricePaid, intLack, intSuffice As Integer
If txtPaid.Text <> "" Or (lstItems.Items.Count = -1) Then
intAmount = lblTotal.Text
intPricePaid = txtPaid.Text
If intAmount > intPricePaid Then
intLack = intAmount - intPricePaid
Do
intSuffice = InputBox("Insufficient amount paid. Please ask Php " & intLack & "." & vbNewLine & "Enter amount:", "Insufficient Amount", MessageBoxButtons.OK, MessageBoxIcon.Error)
intLack = intLack - intSuffice
Loop While intLack > 0
If intLack = 0 Then
MessageBox.Show("Transaction Completed. There is no change. Here is your receipt.", "Transaction success", MessageBoxButtons.OK, MessageBoxIcon.Information)
lstItems.Items.Clear()
lstQuant.Items.Clear()
lstPrice.Items.Clear()
txtPaid.Text = ""
intTotal = 0
lblTotal.Text = "0.00"
ElseIf intLack < 0 Then
MessageBox.Show("Transaction Completed. The change is Php " & intLack * -1 & ". Here is your receipt.", "Transaction success", MessageBoxButtons.OK, MessageBoxIcon.Information)
lstItems.Items.Clear()
lstQuant.Items.Clear()
lstPrice.Items.Clear()
txtPaid.Text = ""
intTotal = 0
lblTotal.Text = "0.00"
End If
ElseIf intAmount = intPricePaid Then
MessageBox.Show("Transaction Completed. There is no change. Here is your receipt.", "Transaction success", MessageBoxButtons.OK, MessageBoxIcon.Information)
lstItems.Items.Clear()
lstQuant.Items.Clear()
lstPrice.Items.Clear()
txtPaid.Text = ""
intTotal = 0
lblTotal.Text = "0.00"
Else
MessageBox.Show("Transaction Completed. The change is Php " & intPricePaid - intAmount & ". Here is your receipt.", "Transaction success", MessageBoxButtons.OK, MessageBoxIcon.Information)
lstItems.Items.Clear()
lstQuant.Items.Clear()
lstPrice.Items.Clear()
txtPaid.Text = ""
intTotal = 0
lblTotal.Text = "0.00"
End If
ElseIf txtPaid.Text = "" Or (lstItems.Items.Count = -1) Then
MessageBox.Show("Please input a value.", "Null value", MessageBoxButtons.OK, MessageBoxIcon.Error)
End If
End Sub
Public Sub DisplayReceipt()
End Sub
End Class