.net 中对象的 ICloneable deepcopy

Question

我正在尝试将使用 ICloneable 的深层复制方法添加到使用 xsd.exe 从 xsd 自动生成的类中。我可以让它在一个简单的级别上工作，但是一旦对象嵌套，那么克隆方法就不起作用了。

我很确定我在 DirectorReturnType 类上的克隆方法有误，但我不知道如何修复它。

任何人都可以提供任何帮助吗？我附上了下面的子和类：

        Dim oDirRetType As New DirectorReturnType
        Dim oDirPerType As New DirectorPersonType

        Dim DirPerTypeT1 As New DirectorPersonType
        Dim DirPerTypeT2 As New DirectorPersonType

        Dim DirRetTypeT1 As New DirectorReturnType
        Dim DirRetTypeT2 As New DirectorReturnType

        Dim AROT1 As New AnnualReturnOfficer
        Dim AROT2 As New AnnualReturnOfficer

这按预期工作，消息“test1”，然后是“test2”：

        'Works
        oDirPerType.Occupation = "test1"
        DirRetTypeT1.Item = oDirPerType.Clone

        oDirPerType.Occupation = "test2"
        DirRetTypeT2.Item = oDirPerType.Clone

        DirPerTypeT1 = DirRetTypeT1.Item
        DirPerTypeT2 = DirRetTypeT2.Item

        MsgBox(DirPerTypeT1.Occupation)
        MsgBox(DirPerTypeT2.Occupation)

如果我随后添加一个AnnualRetunOfficer 类型的额外对象AROTx，那么它会消息“Test2”，然后是“Test2”。

        'Doesnt Work
        oDirPerType.Occupation = "test1"
        oDirRetType.Item = oDirPerType
        AROT1.Item = oDirRetType.Clone

        oDirPerType.Occupation = "test2"
        DirRetTypeT2.Item = oDirPerType
        AROT2.Item = oDirRetType.Clone

        DirRetTypeT1 = AROT1.Item
        DirPerTypeT1 = DirRetTypeT1.Item

        DirRetTypeT2 = AROT2.Item
        DirPerTypeT2 = DirRetTypeT2.Item

        MsgBox(DirPerTypeT1.Occupation)
        MsgBox(DirPerTypeT2.Occupation)

DirectorPersonType：

Partial Public Class DirectorPersonType

Inherits PersonBaseType

Implements ICloneable

Private serviceAddressField As ServiceAddressType

Private dOBField As Date

Private nationalityField As String

Private occupationField As String

Private countryOfResidenceField As String

Private previousNamesField() As PreviousNameType

'''<remarks/>
Public Property ServiceAddress() As ServiceAddressType
    Get
        Return Me.serviceAddressField
    End Get
    Set(value As ServiceAddressType)
        Me.serviceAddressField = value
    End Set
End Property

'''<remarks/>
<System.Xml.Serialization.XmlElementAttribute(DataType:="date")> _
Public Property DOB() As Date
    Get
        Return Me.dOBField
    End Get
    Set(value As Date)
        Me.dOBField = value
    End Set
End Property

'''<remarks/>
Public Property Nationality() As String
    Get
        Return Me.nationalityField
    End Get
    Set(value As String)
        Me.nationalityField = value
    End Set
End Property

'''<remarks/>
Public Property Occupation() As String
    Get
        Return Me.occupationField
    End Get
    Set(value As String)
        Me.occupationField = value
    End Set
End Property

'''<remarks/>
Public Property CountryOfResidence() As String
    Get
        Return Me.countryOfResidenceField
    End Get
    Set(value As String)
        Me.countryOfResidenceField = value
    End Set
End Property

'''<remarks/>
<System.Xml.Serialization.XmlElementAttribute("PreviousNames")> _
Public Property PreviousNames() As PreviousNameType()
    Get
        Return Me.previousNamesField
    End Get
    Set(value As PreviousNameType())
        Me.previousNamesField = value
    End Set
End Property

Public Function Clone() As Object Implements System.ICloneable.Clone

    Return New DirectorPersonType With {.CountryOfResidence = CountryOfResidence, .DOB = DOB, .Forename = Forename, .Nationality = Nationality, .Occupation = Occupation, .OtherForenames = OtherForenames, .PreviousNames = PreviousNames, .ServiceAddress = ServiceAddress, .Surname = Surname, .Title = Title}

End Function

End Class

DirectorReturnType：

Partial Public Class DirectorReturnType

Implements ICloneable

Private itemField As Object

'''<remarks/>
<System.Xml.Serialization.XmlElementAttribute("Corporate",
GetType(CorporateOfficerType)), _
System.Xml.Serialization.XmlElementAttribute("Person", 
GetType(DirectorPersonType))> _
Public Property Item() As Object
    Get
        Return Me.itemField
    End Get
    Set(value As Object)
        Me.itemField = Value
    End Set
End Property

Public Function Clone() As Object Implements System.ICloneable.Clone

    Return New DirectorReturnType With {.Item = Item}

End Function

Answer 1

您的克隆实际上并没有制作一些变量的新副本，而是指向存储在原始类中的现有值。

即这两个变量：

Private serviceAddressField As ServiceAddressType
Private previousNamesField() As PreviousNameType

在您的克隆功能中需要特别注意。

调用ME.MemberwiseClone 来获取实例的新浅拷贝是很整洁的（也许不是完全标准）。然后您必须分别处理您的非标准类型（数组、类）并创建它们的新副本。

类似的东西（请纠正任何错误，但这是一般的想法）

Public Function Clone() As Object Implements ICloneable.Clone
   Dim typClone As DirectorPersonType = Me.MemberwiseClone ' Shallow clone taken and new object created
   Try
      typClone.serviceAddressField = Me.serviceAddressField.Clone ' create a new copy with same value

      typClone.previousNamesField.AddRange(Me.previousNamesField) ' create a new copy with the same values
      ' PreviousNamesField will need some work generating a new array
      ' let me know if you need more detail or a working example

      ' However, I have been corrected and will share that this method is 
      ' definitely superior to AddRange, using LINQ to
      ' create a new list with a copy of the items
       typClone.ListName = Me.ListName.Select(Function(x) x.Clone()).Cast(Of ClassName).ToList

   Catch ex As Exception
         ' catch errors and handle here!
   End Try
   Return typClone
End Function