File-Based Applications: Bethesda Car Rental

	File-Based Applications: Bethesda Car Rental

Cars

Cars are at the center of the rental transactions of our company. A car is the main reason a customer comes to the business. In our application, we will provide all the necessary information related to a car such as its make, model, year, picture, and whether it is available. Because we know that sometimes when renting or choosing a car, a customer may want to know the options available on a particular car, we will also list these basic pieces of information. Finally, we will mark a car as available or not. This will allow the clerk processing an order to know whether the customer can rent the car or not.

We will create two forms related to cars. One form will be used to enter a new car when the company acquires one. On the other hand, when interviewing a customer, if the clerk wants to see a list of the company cars, we will create a form that can help with this, allowing the clerk to navigate among cars for a review.

Practical Learning: Processing Cars

Copy the following pictures to the bin sub-folder inside the main folder of the current project (Save them with their default names):
Return to your programming environment
To add a new form to the application, on the main menu, click Project -> Add Windows Forms
Set the Name to NewCar and press Enter

Design the form as follows:

Control	Text	Name	Other Properties
Label	Text #
TextBox		txtTagNumber
Label	Make:
TextBox		txtMake
Label	Model:
TextBox		txtModel
Label	Year:
TextBox		txtYear
Label	Category:
ComboBox		cboCategory	DropDownStyle: DropDownList
ComboBox		cboCategory	Items:	Economy Compact Standard Full Size Mini Van SUV Truck Van
CheckBox	Cassete Player	chkK7Player	CheckAlign: MiddleRight
CheckBox	DVD Player	chkDVDPlayer	CheckAlign: MiddleRight
CheckBox	CD Player	chkCDPlayer	CheckAlign: MiddleRight
CheckBox	Available	chkAvailable	CheckAlign: MiddleRight
PictureBox		pctCar	SizeMode: CenterImage
Label	Select Car Picture:
ComboBox	none.gif	cboPictures
Button	Add Car	btnAddCar
Button	Close	btnClose	DialogResult: OK
Form			FormBorderStyle: FixedDialog MaximizeBox: False MinimizeBox: False ShowInTaskbar: False

To add a new class to the project, on the main menu, click Project -> Add Class...
Set the Class Name to Car and click Open

Access the Car.cs file and change it as follows:

<Serializable()> Public NotInheritable Class Car
    Public TagNumber As String
    Public Make As String
    Public Model As String
    Public Year As Integer
    Public Category As String
    Public HasK7Player As Integer
    Public HasCDPlayer As Integer
    Public HasDVDPlayer As Integer
    Public PictureName As String
    Public IsAvailable As Integer

    Public Sub New()
        TagNumber = "000-000"
        Make = "Make"
        Model = "Model"
        Year = 1960
        Category = "Small"
        HasK7Player = 0
        HasCDPlayer = 0
        HasDVDPlayer = 0
        PictureName = ""
        IsAvailable = 0
    End Sub

    Public Sub New(ByVal tag As String, ByVal mk As String, _
                   ByVal mdl As String, ByVal yr As Integer, _
                   ByVal cat As String, ByVal k7 As Integer, _
                   ByVal cd As Integer, ByVal dvd As Integer, _
                   ByVal pct As String, ByVal avl As Integer)

        TagNumber = tag
        Make = mk
        Model = mdl
        Year = yr
        Category = cat
        HasK7Player = k7
        HasCDPlayer = cd
        HasDVDPlayer = dvd
        PictureName = pct
        IsAvailable = avl
    End Sub
End Class

Return to the Customers form. Right-click it and click View Code

In the top section of the file, type:

Imports System.IO
Imports System.Runtime.Serialization.Formatters.Soap

Public Class NewCar
    Inherits System.Windows.Forms.Form

    Private lstCars As ArrayList

In the Class Name combo box, select (NewCar Events)

In the Method Name combo box, select Load and implement its event as follows:

Private Sub NewCar_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
        lstCars = New ArrayList
        Dim strFilename As String = "Cars.bcr"
        Dim bcrSoap As SoapFormatter = New SoapFormatter

        If File.Exists(strFilename) Then
            Dim bcrStream As FileStream = New FileStream(strFilename, FileMode.Open, FileAccess.Read, FileShare.Read)
            lstCars = bcrSoap.Deserialize(bcrStream)
            bcrStream.Close()
        Else
            Dim bcrStream As FileStream = New FileStream(strFilename, FileMode.OpenOrCreate, FileAccess.Write, FileShare.Write)
            bcrSoap.Serialize(bcrStream, lstCars)
            bcrStream.Close()
        End If

        ' Locate the director that contains the current application
        Dim dirInfo As DirectoryInfo = New DirectoryInfo(".\\")

        ' Get a reference to each file in that directory
        Dim lstFiles As FileInfo() = dirInfo.GetFiles()

        ' Display the names of the graphics files
        For Each fi As FileInfo In lstFiles
            If fi.Extension.Equals(".gif") Or _
               fi.Extension.Equals(".jpeg") Or _
               fi.Extension.Equals(".jpg") Or _
               fi.Extension.Equals(".bmp") Or _
               fi.Extension.Equals(".png") Then
                cboPictures.Items.Add(fi.Name)
            End If
        Next

        cboPictures.Text = "none.gif"
End Sub

In the Class Name combo box, select cboPictures

In the Method Name combo box, select SelectedIndexChanged and implement the event as follows:

Private Sub cboPictures_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles cboPictures.SelectedIndexChanged
        Me.pctCar.Image = Image.FromFile(cboPictures.Text)
End Sub

In the Class name combo box, select btnAddCar

In the Method Name combo box, select Click and implement it as follows:

Private Sub btnAddCar_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnAddCar.Click
        Dim vehicle As Car = New Car

        vehicle.TagNumber = Me.txtTagNumber.Text
        vehicle.Make = Me.txtMake.Text
        vehicle.Model = Me.txtModel.Text
        vehicle.Year = CInt(Me.txtYear.Text)
        vehicle.Category = Me.cboCategory.Text
        If Me.chkK7Player.Checked = True Then
            vehicle.HasK7Player = 1
        Else
            vehicle.HasK7Player = 0
        End If

        If Me.chkCDPlayer.Checked = True Then
            vehicle.HasCDPlayer = 1
        Else
            vehicle.HasCDPlayer = 0
        End If

        If Me.chkDVDPlayer.Checked = True Then
            vehicle.HasDVDPlayer = 1
        Else
            vehicle.HasDVDPlayer = 0
        End If

        vehicle.PictureName = cboPictures.Text

        If Me.chkAvailable.Checked = True Then
            vehicle.IsAvailable = 1
        Else
            vehicle.IsAvailable = 0
        End If

        lstCars.Add(vehicle)

        Dim strFilename As String = "Cars.bcr"
        Dim bcrSoap As SoapFormatter = New SoapFormatter
        Dim bcrStream As FileStream = New FileStream(strFilename, FileMode.OpenOrCreate, FileAccess.Write, FileShare.Write)
        bcrSoap.Serialize(bcrStream, lstCars)
        bcrStream.Close()

        Me.txtTagNumber.Text = ""
        Me.txtMake.Text = ""
        Me.txtModel.Text = ""
        Me.txtYear.Text = "1960"
        Me.cboCategory.SelectedIndex = 0
        Me.chkK7Player.Checked = False
        Me.chkCDPlayer.Checked = False
        Me.chkDVDPlayer.Checked = False
        cboPictures.Text = "none.gif"
        Me.chkAvailable.Checked = False
        Me.pctCar.Image = Image.FromFile("none.gif")
        Me.txtTagNumber.Focus()
End Sub

Display the first form, Switchboard.vb [Design]. Add a Button to the form and change its properties as follows:
(Name): btnNewCar
Text: New Car
Double-click the New Car button to generate its Click event

Implement the event as follows:

Private Sub btnNewCar_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnNewCar.Click
        Dim car As NewCar = New NewCar
        car.ShowDialog()
End Sub

Execute the application
Create a few cars as follows:
Close the forms and return to your programming environment
To add a new form to the application, on the main menu, click Project -> Add Windows Forms
Set the Name to Cars and press Enter

Design the form as follows:

Control	Text	Name	Other Properties
Label	Make:
TextBox		txtMake
Label	Model:
TextBox		txtModel
Label	Year:
TextBox		txtYear
Label	Category:
TextBox		txtCategory
CheckBox	Cassete Player	chkK7Player	CheckAlign: MiddleRight
CheckBox	DVD Player	chkDVDPlayer	CheckAlign: MiddleRight
CheckBox	CD Player	chkCDPlayer	CheckAlign: MiddleRight
CheckBox	Available	chkAvailable	CheckAlign: MiddleRight
Label	Tag #:
TextBox		txtTagNumber
PictureBox		pctCar
Button	First	btnFirst
Button	Previous	btnPrevious
Button	Next	btnNext
Button	Last	btnLast
Button	Close	btnClose
Form			MaximizeBox: False StartPosition: CenterScreen

Right-click the form and click View Code

In the top section of the file, type:

Imports System.IO
Imports System.Runtime.Serialization.Formatters.Soap

Public Class Cars
    Inherits System.Windows.Forms.Form

    Private lstCars As ArrayList
    Private CurrentPosition As Integer

In the Class Name combo box, select (Cars Events)

In the Method Name combo box, select Load and implement the event as follows:

Private Sub Cars_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
        lstCars = New ArrayList
        CurrentPosition = 0

        Dim strFilename As String = "Cars.bcr"
        Dim bcrSoap As SoapFormatter = New SoapFormatter

        If File.Exists(strFilename) Then
            Dim bcrStream As FileStream = New FileStream(strFilename, FileMode.Open, FileAccess.Read, FileShare.Read)
            lstCars = bcrSoap.Deserialize(bcrStream)

            bcrStream.Close()
            Me.btnFirst_Click(sender, e)
        End If
End Sub

Private Sub ShowCarInformation(ByVal vehicle As Car)
        Me.txtTagNumber.Text = vehicle.TagNumber
        Me.txtMake.Text = vehicle.Make
        Me.txtModel.Text = vehicle.Model
        Me.txtYear.Text = vehicle.Year.ToString()
        Me.txtCategory.Text = vehicle.Category

        If vehicle.HasK7Player = 1 Then
            Me.chkK7Player.Checked = True
        Else
            Me.chkK7Player.Checked = False
        End If

        If vehicle.HasCDPlayer = 1 Then
            Me.chkCDPlayer.Checked = True
        Else
            Me.chkCDPlayer.Checked = False
        End If

        If vehicle.HasDVDPlayer = 1 Then
            Me.chkDVDPlayer.Checked = True
        Else
            Me.chkDVDPlayer.Checked = False
        End If
        Dim strPictureName As String = vehicle.PictureName

        Try
            Me.pctCar.Image = Image.FromFile(vehicle.PictureName)
        Catch exc As OutOfMemoryException
            Me.pctCar.Image = Image.FromFile("none.gif")
        End Try

        If vehicle.IsAvailable = 1 Then
            Me.chkAvailable.Checked = True
        Else
            Me.chkAvailable.Checked = False
        End If
End Sub

In the Class Name combo box, select btnFirst

In the Method Name combo box, select Click and implement the event as follows:

Private Sub btnFirst_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnFirst.Click
        If lstCars.Count = 0 Then Exit Sub

        CurrentPosition = 0
        Dim vehicle As Car = New Car

        vehicle = Me.lstCars(CurrentPosition)

        ShowCarInformation(vehicle)
End Sub

In the Class Name combo box, select btnPrevious

In the Method Name combo box, select Click and implement the event as follows:

Private Sub btnPrevious_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnPrevious.Click
        If lstCars.Count = 0 Then Exit Sub

        If CurrentPosition = 0 Then Exit Sub

        CurrentPosition = CurrentPosition - 1
        Dim vehicle As Car = New Car

        vehicle = lstCars(CurrentPosition)

        ShowCarInformation(vehicle)
End Sub

In the Class Name combo box, select btnNext

In the Method Name combo box, select Click and implement the Click event as follows:

Private Sub btnNext_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnNext.Click
        If lstCars.Count = 0 Then Exit Sub

        If CurrentPosition = lstCars.Count - 1 Then
            Exit Sub
        Else
            CurrentPosition = CurrentPosition + 1

            Dim vehicle As Car = New Car

            vehicle = lstCars(CurrentPosition)

            ShowCarInformation(vehicle)
        End If
End Sub

In the Class Name combo box, select btnLast

In the Method Name combo box, select Click and implement the Click event as follows:

Private Sub btnLast_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnLast.Click
        If lstCars.Count = 0 Then Exit Sub

        CurrentPosition = lstCars.Count - 1
        Dim vehicle As Car = New Car

        vehicle = Me.lstCars(CurrentPosition)

        ShowCarInformation(vehicle)
End Sub

Return to the Cars form. Double-click the Close button and implement its Click event as follows:

Private Sub btnClose_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnClose.Click
        Close()
End Sub

Display the first form, Switchboard.vb [Design]. Add a Button to the form and change its properties as follows:
(Name): btnCarsReview
Text: Car Review
Double-click the New Car button to generate its Click event

Implement the event as follows:

Private Sub btnCarsReview_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnCarsReview.Click
        Dim frmCars As Cars = New Cars
        frmCars.Show()
End Sub

Execute the application and review the list of cars using the Cars form
Close the forms and return to your programming environment


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