Inheritante PBO

aplikasi ini awal nya saya buat untuk memenuhi tugas praktikum pemrograman berprientasi objek.
pada bab inheritance ini aplikasi nya sebagai berikut.
pertama analisa class diagram berikut.

kemudian desain form seperti berikut;

• kemudian beri codding pada class identitas

Public NotInheritable Class Identitas

    Private Nama As String

    Private NIM As Single

    Private Jurusan As String

    Public Property xNama() As String

        Get

            Return Nama

        End Get

        Set(ByVal value As String)

            Nama = value

        End Set

    End Property

    Public Property xNIM() As Integer

        Get

            Return NIM

        End Get

        Set(ByVal value As Integer)

            NIM = value

        End Set

    End Property

    Public Property xJurusan() As String

        Get

            Return Jurusan

        End Get

        Set(ByVal value As String)

            Jurusan = value

        End Set

    End Property

End Class

• codding pada  class angkatan

Public MustInherit Class Angkatan

    Private spp As Integer

    Private THangkatan As Integer

    Public Property xSPP(ByVal THangkatan As Integer) As Integer

        Get

            If THangkatan = 2010 Then

                Return 125000

            ElseIf THangkatan = 2011 Then

                Return 140000

            ElseIf THangkatan = 2012 Then

                Return 160000

            End If

        End Get

        Set(ByVal value As Integer)

            spp = value

        End Set

    End Property

    Public Property xTHangkatan() As Integer

        Get

            Return THangkatan

        End Get

        Set(ByVal value As Integer)

            THangkatan = value

        End Set

    End Property

End Class

• codding pada class bayar

Public Class Bayar

    Inherits Angkatan

    Private Bulan As Integer

    Private Jumlah As Integer

    Public Property xBulan() As Integer

        Get

            Return Bulan

        End Get

        Set(ByVal value As Integer)

            Bulan = value

        End Set

    End Property

    Public Property xJumlah() As Integer

        Get

            Return Jumlah

        End Get

        Set(ByVal value As Integer)

            Jumlah = value

        End Set

    End Property

    Public Function JumlahBayar(ByVal xSPP As Integer) As Integer

        Return xSPP * xBulan

    End Function

End Class

setelah membuat ketiga class tersebut kita tinggal memberi code pada button proses, codding nya sebagai berikut;

 Dim zaqi As New Identitas

        With zaqi

            .xNIM = TextBox1.Text

            .xNama = TextBox2.Text

            .xJurusan = ComboBox1.Text

        End With

        Dim zaki As New Bayar

        With zaki

            .xTHangkatan = ComboBox2.Text

            .xBulan = TextBox3.Text

        End With

        With ListBox1

            .Items.Add("NIM : " & zaqi.xNIM)

            .Items.Add("NAMA    : " & zaqi.xNama)

            .Items.Add("JURUSAN : " & zaqi.xJurusan)

            .Items.Add("ANGKATA : " & zaki.xTHangkatan)

            .Items.Add("SPP  : " & zaki.xSPP(zaki.xTHangkatan))

            .Items.Add("JUMLAH BULAN YG DI BAYAR  : " & zaki.xBulan & " BULAN")

            .Items.Add("JUMLAH BAYAR    : " & zaki.JumlahBayar(zaki.xSPP(zaki.xTHangkatan)))

        End With

codding pada button hapus

        TextBox1.Text = ""
        TextBox2.Text = ""
        TextBox3.Text = ""
        ComboBox1.Text = ""
        ComboBox2.Text = ""
        ListBox1.Items.Clear()