此程序输出﹕
Club: sogo has member:
Alvin, 32
Judy, 28

c_name 指向Strclass之对象﹐这对象内含俱乐部之名称。pa指向ArrayList之对象﹐这对象可包含许多会员(Person)对象。join()程序将Person之对象存入pa所指的ArrayList对象中。
    Club之对象含ArrayList之对象﹐此集合对象(Collections)含有Person之对象﹐表达了「集合／成员」关系。例如﹐x 对象内含a 和b 对象。

    此图表示﹕"sogo"俱乐部共有"Alvin" 和"Judy"两个会员﹐亦即x 是「集合」﹐而a 和b 是「成员」(Member)。
    值得注意﹕这软件是利用已有类别──Strclass及Integer组合成应用类别──Person。再利用Person类别及ArrayList 类别组合成更复杂之应用类别──Club。未来﹐可利用Club及其它类别构筑更大的应用类别﹐依此类推﹐便能创造庞大又可靠的软件了。例如：

''''ex06.bas
Imports System.ComponentModel
Imports System.Drawing
Imports System.WinForms
Imports System.Collections
''''----------------------------------------------------
Class Person
    Private p_name As String
    Private p_age As Integer
    Public Sub New(ByVal na As String, ByVal a As Integer)
        p_name = na
        p_age = a
    End Sub
    Public Sub display()
        Messagebox.Show(Me.p_name + ", " + str(Me.p_age))
    End Sub
End Class

Class Club
    Private c_name As String
    Private pa As ArrayList
   
    Public Sub New(ByVal na As String)
        c_name = na
        pa = New ArrayList()
    End Sub
    Public Sub join(ByVal p As Person)
        pa.Add(p)
    End Sub
    Public Sub display()
        Messagebox.Show("Club: " + Me.c_name + "  has member:")
        Dim p As Person
        For Each p In pa
            p.display()
        Next
    End Sub
End Class
''''----------------------------------------------------
Public Class Form1
    Inherits System.WinForms.Form
   
    Public Sub New()
        MyBase.New()
       
        Form1 = Me
        ''''This call is required by the Win Form Designer.
        InitializeComponent()
        ''''TODO: Add any initialization after the InitializeComponent() call
    End Sub
    ''''Form overrides dispose to clean up the component list.
    Public Overrides Sub Dispose()
        MyBase.Dispose()
        components.Dispose()
    End Sub
#Region " Windows Form Designer generated code "
    ......
#End Region
   Protected Sub Form1_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim x(2) As Club
        x(0) = New Club("sogo")
        x(1) = New Club("gold")
        Dim a As New Person("Alvin", 32)
        Dim b As New Person("Judy", 28)
        Dim c As New Person("Bob", 38)
        x(0).join(a)
        x(0).join(b)
        x(1).join(b)
        x(1).join(c)
        x(0).display()
        x(1).display()
    End Sub
End Class

此程序输出：

Club: sogo has member:
  Alvin, 32
  Judy, 28
Club: gold has member:
  Judy, 28
  Bob, 38

     组合对象x 含"sogo"及"gold"两俱乐部﹐其中"gold"俱乐部拥有两个会员──"Alvin" 及"Judy"﹐而"sogo"俱乐部拥有两位会员──"Judy"及"Bob" 。x(0)代表"sogo"俱乐部﹐s(1)代表"gold"俱乐部﹐所以指令── s(0).join( a ) 表示a 加入"gold"俱乐部﹐成为其会员。n

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