'Program:       Programming Exercise Chapter 10.2
'Programmer:	Joseph Schuman
'Date:			October 2014
'Class:         VendorsForm.vb
'Description:   A form for entering and viewing Vendor objects
'				in a Vendor collection. Uses a Listbox collection.

Public Class vendorForm

    Private Sub addButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles addButton.Click
        ' Create a Vendor object and add it to the collection.
        'Declare a Vendor object

        Dim aVendor As Vendor

        'Declare a boolean variable to aid in testing for a duplicate value and initialize it to False

        Dim FoundBoolean As Boolean = False
        
        'Validate that all text boxes have data in them
        If nameTextBox.Text <> "" Then
            If phoneTextBox.Text <> "" Then
                If contactTextBox.Text <> "" Then
                    If emailTextBox.Text <> "" Then
                        ' Declare and instantiate a new Vendor.
                        Try
                            'Check for Duplicate vendor

                            With vendorsListBox
                                'Check the list box for dupicates using a loop.
                                For indexInteger As Integer = 0 To .Items.Count - 1
                                    'Instantite a vendor object with the current item in the check box.
                                    'Change the list item in the check box to a vendor object and store in aVendor.
                                    aVendor = CType(.Items.Item(indexInteger), Vendor)
                                    'Check for duplicate in the check box.
                                    If nameTextBox.Text.ToLower = aVendor.Name.ToLower Then
                                        'Set FoundBoolean to true and Exit.
                                        FoundBoolean = True
                                        Exit For
                                    End If
                                    'Otherwise go to the next item in the list box.

                                Next indexInteger
                            End With

                            'If not found then create aVendor object and add it to the items collection
                            If Not foundBoolean Then
                                'Create the vendor object in the class by calling the constructor function
                                aVendor = New Vendor(nameTextBox.Text, phoneTextBox.Text, _
                                contactTextBox.Text, emailTextBox.Text)

                                'Add the vendor object to the Items collection.

                                vendorsListBox.Items.Add(aVendor)

                                'Display the count in countLabel.Text

                                countLabel.Text = vendorsListBox.Items.Count.ToString

                                ' Clear the text boxes.
                                With nameTextBox
                                    .Clear()
                                    .Focus()
                                End With
                                phoneTextBox.Clear()
                                contactTextBox.Clear()
                                emailTextBox.Clear()

                            Else 'Duplicate name found
                                MessageBox.Show("Duplicate Vendor name." & _
                                  ControlChars.NewLine & nameTextBox.Text & _
                                  "  Not Added.", "A Collection of Vendors")
                                With nameTextBox
                                    .Clear()
                                    .Focus()
                                End With
                                phoneTextBox.Clear()
                                contactTextBox.Clear()
                                emailTextBox.Clear()
                            End If
                            'Add the Catch statement to process any errors during the add

                        Catch Ex As Exception
                            MessageBox.Show("Error: " & Ex.Message & ControlChars.NewLine & "Unable To Process", "Error", _
                                            MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
                            With nameTextBox
                                .SelectAll()
                                .Focus()
                            End With
                        End Try

                    Else
                        With emailTextBox
                            .SelectAll()
                            .Focus()
                        End With
                        MessageBox.Show("Please enter an e-mail address.", _
                          "A Collection of Vendors")
                    End If
                Else
                    With contactTextBox
                        .SelectAll()
                        .Focus()
                    End With
                    MessageBox.Show("Please enter a contact person.", _
                      "A Collection of Vendors")
                End If
            Else
                With phoneTextBox
                    .SelectAll()
                    .Focus()
                End With
                MessageBox.Show("Please enter a phone number.", _
                  "A Collection of Vendors")
            End If
        Else
            With nameTextBox
                .SelectAll()
                .Focus()
            End With
            MessageBox.Show("Please enter a name.", _
              "A Collection of Vendors")
        End If

    End Sub

    Private Sub removeButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles removeButton.Click
        ' Remove selected item from the collection.

        With vendorsListBox
            If .SelectedIndex <> -1 Then
                'Remove the current item from the list box
                .Items.RemoveAt(.SelectedIndex)

                ' Display the count.
                countLabel.Text = .Items.Count.ToString

            Else
                MessageBox.Show("Select a Vendor from the list.", _
                    "A Collection of Vendors")
            End If
        End With
    End Sub

    Private Sub displayButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles displayButton.Click
        ' Display the information for the selected Vendor.
        Dim aVendor As Vendor
        Dim messageString As String

        With vendorsListBox
            If .SelectedIndex <> -1 Then
                ' Get the selected vendor item from the collection.

                aVendor = CType(.Items.Item(.SelectedIndex), Vendor)

                'Display the informstion from the aVendor object
                messageString = "The information for the selected company: is: " & _
                                    ControlChars.NewLine & "Name    : " & aVendor.Name & _
                                    ControlChars.NewLine & "Phone   : " & aVendor.Phone & _
                                    ControlChars.NewLine & "Contact : " & aVendor.Contact & _
                                    ControlChars.NewLine & "E-Mail  : " & aVendor.EMail
                MessageBox.Show(messageString, "A Collection of Vendors")
            Else
                MessageBox.Show("Select a Vendor from the list.", _
                  "A Collection of Vendors")
            End If
        End With
    End Sub

End Class

'Program:   	Programming Exercise Chapter 10.2
'Programmer:    Joseph Schuman
'Date:			October 2014
'Class:         VendorClass.vb
'Description:	Create a Vendor class.

Public Class Vendor

    ' Private property variables.
    Private nameString As String
    Private phoneString As String
    Private contactString As String
    Private emailString As String

    ' Class constructor.
    Public Sub New(ByVal nameString As String, _
        ByVal phoneString As String, ByVal contactString As String, ByVal emailString As String)
        ' Create a Vendor object.

        Me.Name = nameString
        Me.Phone = phoneString
        Me.Contact = contactString
        Me.EMail = emailString
    End Sub

    ' Property procedures.
    Public Property Name() As String
        Get
            Return nameString
        End Get
        Set(ByVal Value As String)
            nameString = Value
        End Set
    End Property

    Public Property Phone() As String
        Get
            Return phoneString
        End Get
        Set(ByVal Value As String)
            phoneString = Value
        End Set
    End Property

    Public Property Contact() As String
        Get
            Return contactString
        End Get
        Set(ByVal Value As String)
            contactString = Value
        End Set
    End Property

    Public Property EMail() As String
        Get
            Return emailString
        End Get
        Set(ByVal Value As String)
            emailString = Value
        End Set
    End Property

    ' Add the Procedure in the Vendor class to override the ToString function.

    Public Overrides Function ToString() As String
        'Return the Name property for this object's ToString method.

        Return nameString
    End Function
End Class