Reflection - SetValue of array within class?

Posted by Jaymz87 on Stack Overflow See other posts from Stack Overflow or by Jaymz87
Published on 2009-02-19T11:11:28Z Indexed on 2010/03/22 3:41 UTC
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OK, I've been working on something for a while now, using reflection to accomplish a lot of what I need to do, but I've hit a bit of a stumbling block...

I'm trying to use reflection to populate the properties of an array of a child property... not sure that's clear, so it's probably best explained in code:

Parent Class:

Public Class parent
    Private _child As childObject()
    Public Property child As childObject()
        Get
            Return _child
        End Get
        Set(ByVal value As child())
            _child = value
        End Set
    End Property
End Class

Child Class:

Public Class childObject
    Private _name As String
    Public Property name As String
        Get
            Return _name
        End Get
        Set(ByVal value As String)
            _name = value
        End Set
    End Property

    Private _descr As String
    Public Property descr As String
        Get
            Return _descr
        End Get
        Set(ByVal value As String)
            _descr = value
        End Set
    End Property
End Class

So, using reflection, I'm trying to set the values of the array of child objects through the parent object...

I've tried several methods... the following is pretty much what I've got at the moment (I've added sample data just to keep things simple):

    Dim Results(1) As String

    Results(0) = "1,2"
    Results(1) = "2,3"
    Dim parent As New parent

    Dim child As childObject() = New childObject() {}
    Dim PropInfo As PropertyInfo() = child.GetType().GetProperties()
    Dim i As Integer = 0
    For Each res As String In Results 
        Dim ResultSet As String() = res.Split(",")
        ReDim child(i)

        Dim j As Integer = 0
        For Each PropItem As PropertyInfo In PropInfo
            PropItem.SetValue(child, ResultSet(j), Nothing)
            j += 1
        Next
        i += 1
    Next
    parent.child = child

This fails miserably on PropItem.SetValue with ArgumentException: Property set method not found.

Anyone have any ideas?

@Jon :-

Thanks, I think I've gotten a little further, by creating individual child objects, and then assigning them to an array... The issue is now trying to get that array assigned to the parent object (using reflection).

It shouldn't be difficult, but I think the problem comes because I don't necessarily know the parent/child types. I'm using reflection to determine which parent/child is being passed in. The parent always has only one property, which is an array of the child object. When I try assigning the child array to the parent object, I get a invalid cast exception saying it can't convert Object[] to .

EDIT: Basically, what I have now is:

Dim PropChildInfo As PropertyInfo() = ResponseObject.GetType().GetProperties()
For Each PropItem As PropertyInfo In PropChildInfo
    PropItem.SetValue(ResponseObject, ResponseChildren, Nothing)
Next

ResponseObject is an instance of the parent Class, and ResponseChildren is an array of the childObject Class.

This fails with: Object of type 'System.Object[]' cannot be converted to type 'childObject[]'.

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