excel - 变量类型的自定义类的父对象

Question

我认为我正在用 VBA 编写一个相当复杂的东西，尽管我做了很多研究，但到目前为止我还无法找到解决我的问题的方法。不幸的是我不是专家:)

我有两门课，例如clsBuilding 和 clsFactory，它们都有一个 clsHeatDemand 实例。现在我正在尝试实现一个 parent-Property 来访问计算所需的基类中的一些值，基于 this主意。

Friend Property Get Parent() As clsBuilding
    Set Parent = ObjFromPtr(parentPtr)
End Property
Friend Property Set Parent(obj As clsBuilding)
    parentPtr = ObjPtr(obj)
End Property

我现在的问题是，parent 可以是两种不同的类型，即使它们具有我需要的相同参数。所以我想问的是是否有一种方法可以将实例简单地作为 obj As Object 移交并仍然访问其属性？

我也尝试过使用 Interfaces，但如果有其他更简单的解决方案，我会很高兴。

Answer 1

不知道对你有没有帮助，你看看吧。

' 具有不同父级的类

Option Explicit

Private m_parent As Variant

Public Property Get Parent() As Variant
    Set Parent = m_parent
End Property

Public Property Set Parent(ByVal vNewValue As Variant)
    Set m_parent = vNewValue
End Property

Public Function Name()
    If TypeName(m_parent) = "ParentA" Then
        Name = m_parent.Name
    Else
        Err.Raise 123, "Parent doesn't have Name"
    End If
End Function

Public Function Height()
    If TypeName(m_parent) = "ParentB" Then
        Height = m_parent.Height
    Else
        Err.Raise 456, "Parent doesn't have Height"
    End If
End Function

' 父级 A

Public Name As String

Public Age As Integer

' 父级B

Public Height As Double

Public Weight As Double

'测试

Sub test()
    Dim c As Class
    Set c = New Class

    Dim pa As ParentA
    Set pa = New ParentA
    pa.Age = 5
    pa.Name = "Parent A"

    Dim pb As ParentB
    Set pb = New ParentB
    pb.Height = 15.5
    pb.Weight = 50.5

    Set c.Parent = pa
    Debug.Print c.Name


    Set c.Parent = pb
    Debug.Print c.Height
    Debug.Print c.Name
End Sub