ublic Class Form1
Private Sub writeCustomers()
'write to file
Dim sw As System.IO.StreamWriter
sw = System.IO.File.CreateText("Customers.txt")
'write number customers
sw.WriteLine(numCustomers)
'write customers
For i As Integer = 0 To numCustomers - 1
sw.WriteLine(mkstrng(Customers(i)))
Next
'close file
sw.Close()
End Sub
Private Sub ReadyNextCustomer()
tbName.Clear()
tbPhone.Clear()
tbAddress.Clear()
tbBalance.Clear()
tbName.Select()
End Sub
Private Sub loadCustomers()
'read from file
Dim sr As System.IO.StreamReader
sr = System.IO.File.OpenText("Customers.txt")
'read number customers
Dim n As Integer = sr.ReadLine
'read customers
ReDim Customers(0)
Dim custStr As String = ""
Dim fields() As String
numCustomers = 0
For i As Integer = 1 To n
ReDim Preserve Customers(numCustomers + 1)
custStr = sr.ReadLine
fields = custStr.Split(","c)
With Customers(numCustomers)
.Name = fields(0)
.Phone = fields(1)
.Address = fields(2)
.InitialBalance = fields(3)
.Balance = fields(4)
End With
numCustomers += 1
Next
'close file
sr.Close()
End Sub
Private Sub showCustomers()
Dim fmtStr As String = "{0,-12}{1,6}"
'go through array and display each customer
lbCustomers.Items.Clear()
lbCustomers1.Items.Clear()
lbCustomers2.Items.Clear()
lbCustomers3.Items.Clear()
For i As Integer = 0 To numCustomers - 1
With Customers(i)
Dim dispStr As String = String.Format(fmtStr, .Name,
FormatCurrency(.Balance))
lbCustomers.Items.Add(dispStr)
lbCustomers1.Items.Add(dispStr)
lbCustomers2.Items.Add(dispStr)
lbCustomers3.Items.Add(dispStr)
End With
Next
End Sub
Private Function makeStatement(ByVal c As Customer, ByVal month
As Integer) As statement
Dim s As statement
s.ChargeList = New List(Of Charge)
s.paymentlist = New List(Of payment)
s.SCustomer = c
Dim sn As String = c.Name
Dim m As Integer = month
Dim i As Integer
For i = 0 To numCharges - 1
If sn = Charges(i).customername Then
If Charges(i).ChargeDate.Month = m Then
s.ChargeList.Add(Charges(i))
End If
End If
Next
For i = 0 To numpayments - 1
If sn = payments(i).CustomerName Then
If payments(i).PaymentDate.Month = m Then
s.paymentlist.Add(payments(i))
End If
End If
Next
Return s
End Function
Private Sub showStatment(ByVal s As statement)
Dim fmtStr As String = "{0,-20}{1,-20}"
Dim fmtstr1 As String = "{0,15}"
Dim fmtstr2 As String = "{0,-12}{1,-10}{2,-10}"
lbStatement.Items.Add(String.Format(fmtStr, "Customer",
selectedCustomer.Name))
lbStatement.Items.Add(String.Format(fmtStr, "Address",
selectedCustomer.Address))
Dim ib As Double
If selectedCustomer.InitialBalance = "" Then
ib = 0
Else
ib = selectedCustomer.InitialBalance
End If
lbStatement.Items.Add(String.Format(fmtStr, "Initial
Balance", FormatCurrency(ib)))
lbStatement.Items.Add(String.Format(fmtStr, "Ending
Balance", FormatCurrency(selectedCustomer.Balance)))
lbStatement.Items.Add("")
lbStatement.Items.Add(String.Format(fmtstr1, "Charges"))
For Each c As Charge In s.ChargeList
Dim a As String =
FormatCurrency(FormatCurrency(c.ChargeAmount))
lbStatement.Items.Add(String.Format(fmtstr2, c.ItemName,
a, c.ChargeDate.ToShortDateString))
Next
lbStatement.Items.Add("")
lbStatement.Items.Add(String.Format(fmtstr1, "Payments"))
For Each p As payment In s.paymentlist
Dim a As String =
FormatCurrency(FormatCurrency(p.PaymentAmount))
lbStatement.Items.Add(String.Format(fmtStr, a,
p.PaymentDate.ToShortDateString))
Next
End Sub
Private Sub btnAddItem_Click(ByVal sender As System.Object,
ByVal e As System.EventArgs) Handles btnAddItem.Click
Dim newItem As Item
With newItem
.itemName = tbItem.Text
.ItemCost = tbPrice.Text
End With
'clear text boxes
tbItem.Clear()
tbPrice.Clear()
tbItem.Select()
'add new item to array
NumItems += 1
ReDim Preserve StoreItems(NumItems)
StoreItems(NumItems - 1) = newItem
'save items
saveItems()
'display store items
showitems()
End Sub
Private Sub saveItems()
Dim sveItem As Item
Dim sw As System.IO.StreamWriter
sw = System.IO.File.CreateText("items.txt")
sw.WriteLine(NumItems)
For i As Integer = 0 To NumItems - 1
sveItem = StoreItems(i)
sw.WriteLine(mkStr(sveItem))
Next
sw.Close()
End Sub
Private Sub showitems()
lbitems.Items.Clear()
For i As Integer = 0 To NumItems - 1
With StoreItems(i)
Dim n As String = .itemName
Dim c As String = FormatCurrency(.ItemCost)
Dim dispItem As String = String.Format("{0,-12}{1,7}", n, c)
lbitems.Items.Add(dispItem)
End With
Next
End Sub
Private Sub Form1_Load(ByVal sender As Object, ByVal e As
System.EventArgs) Handles Me.Load
'read customer file and populate customers array
loadCustomers()
showCustomers()
'read charges and show them
readcharges()
showcharges()
'read items and show them
loaditems()
showitems()
'read payments and show them
loadPayments()
showPayments()
End Sub
Private Sub loaditems()
Dim sr As System.IO.StreamReader
sr = System.IO.File.OpenText("Items.txt")
NumItems = sr.ReadLine
Dim nxtItem As Item, x As String, fields() As String
ReDim StoreItems(NumItems)
For i As Integer = 0 To NumItems - 1
x = sr.ReadLine
fields = x.Split(","c)
With nxtItem
.itemName = fields(0)
.ItemCost = fields(1)
End With
StoreItems(i) = nxtItem
Next
sr.Close()
showitems()
End Sub
Private Sub loadpayments()
Dim sr As System.IO.StreamReader
sr = System.IO.File.OpenText("Payments.txt")
Dim nxtPayment As payment, x As String, fields() As String
'read number of payments
numpayments = sr.ReadLine
ReDim payments(numpayments)
For i As Integer = 0 To numpayments - 1
x = sr.ReadLine
fields = x.Split(","c)
With nxtPayment
.CustomerName = fields(0)
.PaymentAmount = fields(1)
.PaymentDate = fields(2)
End With
payments(i) = nxtPayment
Next
sr.Close()
End Sub
Private Sub showpayments()
Dim fmtstr As String = "{0,-15}{1,-10}{2,-10}"
lbPayments.Items.Clear()
For i As Integer = 0 To numpayments - 1
With payments(i)
Dim displayStr As String
displayStr = String.Format(fmtstr, .CustomerName,
.PaymentAmount, .PaymentDate.ToShortDateString, .PaymentAmount,
.PaymentDate)
lbPayments.Items.Add(displayStr)
End With
Next
End Sub
Private Sub btnAddCharge_Click(ByVal sender As System.Object,
ByVal e As System.EventArgs) Handles btnAddCharge.Click
Dim newCharge As Charge
With newCharge
'get item
Dim itemIndex As Integer = lbitems.SelectedIndex
If itemIndex >= 0 And itemIndex <= NumItems - 1 Then
.ItemName = StoreItems(itemIndex).itemName
.ChargeAmount = StoreItems(itemIndex).ItemCost
Else
MsgBox("Select an item")
Exit Sub
End If
'get customer
Dim customerIndex As Integer =
lbCustomers1.SelectedIndex
If customerIndex >= 0 And customerIndex <= numCustomers
- 1 Then
.customername = Customers(customerIndex).Name
.ChargeDate = Today.ToShortDateString
‘add item cost to customer balance
**
'save customers to file
writeCustomers()
showCustomers()
'show new balance
tbSaleBalance.Text =
Customers(customerIndex).Balance
Else
MsgBox("Select a customer")
Exit Sub
End If
End With
numCharges += 1
ReDim Preserve Charges(numCharges)
Charges(numCharges - 1) = newCharge
'save charges
savecharges()
'show charges
showcharges()
End Sub
Private Sub savecharges()
'array charges -> text file charges.txt
Dim sw As System.IO.StreamWriter
sw = System.IO.File.CreateText("Charges.txt")
sw.WriteLine(numCharges)
Dim i As Integer
For i = 0 To numCharges - 1
With Charges(i)
‘make charges(i) into comma delimited string and
‘write to file
**
End With
Next
sw.Close()
End Sub
Private Sub readcharges()
'text file charges.txt -> array charges
Dim sr As System.IO.StreamReader
sr = System.IO.File.OpenText("Charges.txt")
numCharges = sr.ReadLine
Dim i As Integer
ReDim Charges(numCharges)
For i = 0 To numCharges - 1
With Charges(i)
Dim fields() As String = sr.ReadLine.Split(","c)
‘populate structure variables with fields
**
End With
Next
sr.Close()
End Sub
Private Sub showcharges()
Dim i As Integer
lbCharges.Items.Clear()
Dim fmtStr As String = "{0,-15}{1,-15}{2,-8}{3,8}"
For i = 0 To numCharges - 1
With Charges(i)
Dim c As String = .customername
Dim itm As String = .ItemName
Dim a As String = FormatCurrency(.ChargeAmount)
Dim d As String = .ChargeDate.ToShortDateString
Dim s As String = String.Format(fmtStr, c, itm, a,
d)
lbCharges.Items.Add(s)
End With
Next
End Sub
Private Sub lbCustomers_SelectedIndexChanged_1(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
lbCustomers.SelectedIndexChanged
Dim custIdx As Integer = lbCustomers.SelectedIndex
'MsgBox(custIdx & "," & numCustomers)
'display customer in text boxes
With Customers(custIdx)
tbName.Text = .Name
tbPhone.Text = .Phone
tbAddress.Text = .Address
tbBalance.Text = .Balance
End With
'remove customer from Customers
For k As Integer = custIdx To numCustomers - 2
Customers(k) = Customers(k + 1)
Next
numCustomers -= 1
ReDim Preserve Customers(numCustomers)
showCustomers()
writeCustomers()
End Sub
Private Sub btnAdd_Click(ByVal sender As System.Object, ByVal e
As System.EventArgs) Handles btnAdd.Click
'Create new customer
numCustomers += 1
ReDim Preserve Customers(numCustomers - 1)
'populate field variables of new customer
With Customers(numCustomers - 1)
.Name = tbName.Text
.Phone = tbPhone.Text
.Address = tbAddress.Text
.Balance = 0
'add name to listbox
lbCustomers.Items.Add(.Name)
End With
writeCustomers()
'ready for next customer
ReadyNextCustomer()
End Sub
Private Sub btnCharges_Click(ByVal sender As System.Object,
ByVal e As System.EventArgs)
readcharges()
showcharges()
End Sub
Private Sub lbCustomers2_SelectedIndexChanged(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
lbCustomers2.SelectedIndexChanged
Dim payingCustomer As Customer
'get customer and fill textboxes
payingCustomer = Customers(lbCustomers2.SelectedIndex)
With payingCustomer
tbAccountName.Text = .Name
tbAccountBalance.Text = .Balance
tbAccountAddress.Text = .Address
End With
'set label on statement
selectedCustomer = lbCustomers.SelectedItem
lblStatement.Text &= " - " & selectedCustomer.Name
End Sub
Private Sub btnPayOK_Click(ByVal sender As System.Object, ByVal
e As System.EventArgs) Handles btnPayOK.Click
Dim curPayment As payment
'fill payment fields with textboxes
With curPayment
**
End With
'adjust customer balance
Customers(lbCustomers2.SelectedIndex).Balance -=
CDbl(tbPayment.Text)
‘Redimension Payments array and add curPayment
‘save payments to text file and show in listbox
End Sub
Private Sub savePayments()
Dim nxtPayment As payment, payStr As String
Dim sw As System.IO.StreamWriter
sw = System.IO.File.CreateText("Payments.txt")
'write number payments
**
'for each payment
For i As Integer = 0 To numpayments - 1
'build comma delimited string
**
Next
sw.Close()
End Sub
Private Sub lbMonths_SelectedIndexChanged(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
lbMonths.SelectedIndexChanged
selectedmonth = lbMonths.SelectedIndex + 1
textMonth = lbMonths.SelectedItem
lblStatement.Text = "Statement - " & selectedCustomer.Name &
" - " & lbMonths.SelectedItem
Dim s As statement = makeStatement(selectedCustomer,
selectedmonth)
showStatment(s)
End Sub
Private Sub lbCustomers3_SelectedIndexChanged(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
lbCustomers3.SelectedIndexChanged
selectedCustomer = Customers(lbCustomers3.SelectedIndex)
End Sub
Private Sub lbitems_SelectedIndexChanged(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
lbitems.SelectedIndexChanged
tbSaleItem.Text = StoreItems(lbitems.SelectedIndex).itemName
tbSalePrice.Text =
StoreItems(lbitems.SelectedIndex).ItemCost
End Sub
Private Sub lbCustomers1_SelectedIndexChanged(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
lbCustomers1.SelectedIndexChanged
tbSaleCustomer.Text =
Customers(lbCustomers1.SelectedIndex).Name
tbSaleBalance.Text =
Customers(lbCustomers1.SelectedIndex).Balance
End Sub
Private Sub btnPrint_Click(ByVal sender As System.Object, ByVal
e As System.EventArgs) Handles btnPrint.Click
pdStatement.Print()
End Sub
Private Sub pdStatement_PrintPage(ByVal sender As System.Object,
ByVal e As System.Drawing.Printing.PrintPageEventArgs) Handles
pdStatement.PrintPage
Dim strFmt As String = "{0,5}{1,-20}{2,-25}{3,-15}",
printLine As String
Dim m As Integer = lbStatement.Items.Count - 1, i As Integer
Dim curY As Integer = 20, curx As Integer = 20
e.Graphics.DrawString(textMonth & " Statement for " &
selectedCustomer.Name, New Font("Courier New", 14, _
FontStyle.Bold), Brushes.Black, curx, curY)
curY += 30
For i = 0 To m - 1
With lbStatement.Items(i)
printLine = lbStatement.Items(i)
e.Graphics.DrawString(printLine, New Font("Courier
New", 10, _
FontStyle.Bold), Brushes.Black, curx, curY)
End With
curY += 20
Next
End Sub
Private Sub pdCustomers_PrintPage(ByVal sender As System.Object,
ByVal e As System.Drawing.Printing.PrintPageEventArgs) Handles
pdCustomers.PrintPage
Dim strFmt As String = "{0,-15}{1,-20}{2,-12}", printLine As
String
Dim i As Integer
Dim curY As Integer = 20, curx As Integer = 20
e.Graphics.DrawString("Customer List", New Font("Courier
New", 14, _
FontStyle.Bold), Brushes.Black, curx, curY)
curY += 30
For i = 0 To numCustomers - 1
With Customers(i) 'ith customer
printLine = String.Format(strFmt, .Name, .Address,
.Phone)
e.Graphics.DrawString(printLine, New Font("Courier
New", 10, _
FontStyle.Bold), Brushes.Black, curx, curY)
End With
curY += 20
Next
End Sub
Private Sub btnPrintCustomers_Click(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
btnPrintCustomers.Click
pdCustomers.Print()
End Sub
End Class
Module Globals
#Region "Customers"
Public Structure Customer
Dim Name As String
Dim Phone As String
Dim Address As String
Dim InitialBalance As String
Dim Balance As Double
End Structure
Public Customers() As Customer
Public numCustomers As Integer
Public Function mkstrng(ByVal c As Customer) As String
Dim s As String
With c
s = .Name & "," & .Phone & "," & .Address & _
"," & .InitialBalance & "," & .Balance
End With
Return s
End Function
Public Function showCust(ByVal c As Customer) As String
Dim s As String
With c
s = .Name & " - " & .Balance
End With
Return s
End Function
#End Region
#Region "Sales"
'item structure
Public Structure Item
Dim itemName As String
Dim ItemCost As Double
End Structure
Public StoreItems() As Item
Public NumItems As Integer
Public Function mkStr(ByVal x As Item) As String
With x
Return .itemName & "," & .ItemCost
End With
End Function
'charge structure
Structure Charge
Dim customername As String
Dim ItemName As String
Dim ChargeDate As Date
Dim ChargeAmount As Double
End Structure
Public Charges() As Charge
Public numCharges As Integer
#End Region
#Region "Accounts"
'payments
Public Structure payment
Dim CustomerName As String
Dim PaymentAmount As Double
Dim PaymentDate As Date
End Structure
Public payments() As payment
Public numpayments As Integer
'statement
Public Structure statement
Dim SCustomer As Customer
Dim statementMonth As String
'charges and payments within statement month
'statement written to text file named SCustomer &
statementMonth & .txt
Dim ChargeList As List(Of Charge)
Dim paymentlist As List(Of payment)
End Structure
Public statements() As String 'name of file
Public numStatements As Integer
Public selectedCustomer As Customer
Public selectedmonth As Integer
Public textMonth As String
#End Region
End Module