Class Desk
    Protected dSize As Double
    Public Sub Create()
        dSize = Room.GetMother().GetSize() * 0.18
    End Sub
    Public Function GetSize() As Double
        GetSize = dSize
    End Function
End Class
''''----------------------------------------------------
Class MyRoom
    Inherits Room
    Private rd As New Desk()
   
    Public Sub New()
        Me.Create()
    End Sub
    Public Overrides Sub Create()
        MyBase.Create()
        rSize = 100
        rd.Create()
    End Sub
    Public Sub Show()
        MessageBox.Show("Room Size: " + str(rSize))
        MessageBox.Show("Desk Size: " + str(rd.GetSize()))
    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 r As New MyRoom()
        r.Show()
    End Sub
End Class

此程序输出：
               Room Size: 100
               Desk Size:  18

像指令── dSize = Room.GetMother().GetSize() * 0.18﹐已挪到新设的Create()程序里。待母对象完全建好了﹐才会呼叫这Create()程序﹐GetSize() 就能取得正确值了。MyRoom的New()呼叫Create()程序时﹐母子对象皆已建造完成了。Create()内部依人们的习惯来设定对象之值，例如建立母子对象之关系。

如此就不会出问题了。
    New()与Create()分离之后，MyRoom类别里的指令：

Class MyRoom
    Inherits Room
    Private rd As New Desk()
   
    Public Sub New()
        Me.Create()
    End Sub
........

也能写为：
Class MyRoom
    Inherits Room
    Private rd As Desk
   
    Public Sub New()
        rd = New Desk()
        Me.Create()
    End Sub
........

只要确保Desk类别的指令──
      dSize = Room.GetMother().GetSize() * 0.18

是在MyRoom类别的指令──
      rSize = 100

之后执行即可了。
    上述的子对象是透过Shared 程序来取得母对象的参考值﹐然后才跟母对象沟通。如果不透过Shared程序，也可以采取下述方法：

''''ex04.bas
Imports System.ComponentModel
Imports System.Drawing
Imports System.WinForms
''''----------------------------------------------------
Class Room
    Protected rSize As Double
   
    Public Overridable Sub Create()
    End Sub
    Public Function GetSize() As Double
        GetSize = rSize
    End Function
End Class

Class Desk
    Protected dSize As Double
    Protected myMother As Room
   
    Public Sub Create(ByVal mo As Room)
        myMother = mo
        dSize = myMother.GetSize() * 0.18
    End Sub
    Public Function GetSize() As Double
        GetSize = dSize
    End Function
End Class
''''----------------------------------------------------
Class MyRoom
    Inherits Room
    Private rd As Desk
   
    Public Sub New()
        rd = New Desk()
        Me.Create()
    End Sub
    Public Overrides Sub Create()
        rSize = 100
        rd.Create(Me)
    End Sub
    Public Sub Show()
        MessageBox.Show("Room Size: " + str(rSize))
        MessageBox.Show("Desk Size: " + str(rd.GetSize()))
    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 r As New MyRoom()
        r.Show()
    End Sub
End Class

此程序输出：
               Room Size: 100
               Desk Size:  18

Desk之对象含个参考 myMother ﹐指向其母对象。这项关系是在母子对象皆建好时﹐才由Create()程序所建立的。于是﹐建立出母子对象之关系﹕

综上所述，当MyRoom类别使用如下指令──
 Private rd As New Desk()

时，才必须把New()与Create()分离。如果使用如下指令──

Private rd As Desk
Public Sub New()
    rd = New Desk()
    .....
End Sub
 
就不必分离了，原因是：New()与Create()的执行顺序是一致的，例如两者可合并如下的VB程序：

''''ex05.bas
Imports System.ComponentModel
Imports System.Drawing
Imports System.WinForms
''''----------------------------------------------------
Class Room
    Protected rSize As Double
   
    Public Function GetSize() As Double
        GetSize = rSize
    End Function
End Class

Class Desk
    Protected dSize As Double
    Protected myMother As Room
   
    Public Sub New(ByVal mo As Room)
        myMother = mo
        dSize = myMother.GetSize() * 0.18
    End Sub
    Public Function GetSize() As Double
        GetSize = dSize
    End Function
End Class
''''----------------------------------------------------
Class MyRoom
    Inherits Room
    Private rd As Desk
   
    Public Sub New()
        rSize = 100
        rd = New Desk(Me)
    End Sub
    Public Sub Show()
     &

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