[Jcframework-info] Mapping contained classes

[Richard B. <rb...@ar...>]

(This is a copy of a message posted on the help forum)

Hi everyone,

It is now possible to map properties of classes contained with a 
persistent class without actually mapping the contained class itself.

Since .NET structures themselves cannot be mapped (as they are value 
types and updating member properties is difficult) you can do something 
like the following:

Public Class SomeStruct
Private _partA As String
Private _parent As AToMSFramework.CPersistentObject

Public Property PartA() As String
Get
Return _partA
End Get
Set(ByVal Value As String)
_partA = Value
If Not _parent Is Nothing Then
_parent.SetDirtyFlag()
End If
End Set
End Property

Friend Property Parent() As AToMSFramework.CPersistentObject
Get
Return _parent
End Get
Set(ByVal Value As AToMSFramework.CPersistentObject)
_parent = Value
End Set
End Property
End Class

-------------
Public Class Class1
Inherits CPersistentObject

Private _ss As SomeStruct

Public Property Struct1() As SomeStruct
Get
Return _ss
End Get
Set(ByVal Value As SomeStruct)
_ss = Value
SetDirtyFlag()
End Set
End Property

Public Overrides Function getNewObject() As AToMSFramework.CPersistentObject
Return New Class1
End Function

Public Overrides Function IsValid() As Boolean
Return True
End Function

Public Sub New()
_ss = New SomeStruct
_ss.Parent = Me
End Sub
End Class
-----------
<class name="Class1" table="xx" database="db1">
<attribute name="OIDValue" column="oid" key="primary"/>
<attribute name="Struct1.PartA" column="partA" />
</class>
--------

In your code you can now do

Dim c1 As New Class1
c1.Struct1.PartA = "AA"
c1.Save()

or

c1.OIDValue = "000000420001"
c1.Retrieve(c1)
Debug.WriteLine(c1.Struct1.PartA)

and everything will work correctly.


The code is currently in CVS and will be included in the next release.

- Richard