Derived TreeNode LoadViewState not firing



We're experiencing a problem with LoadViewState not getting fired for
a derived TreeNode class. We derived the TreeNode class in order to
add CSSClass property and the initial Page_Load displays the TreeView
and derived TreeNodes correctly. However, upon PostBack, we get the
'Failed to Load ViewState....' error and when we set breakpoints, it
never stops on our LoadViewState override. Also, the SaveViewState
definitely gets invoked. We've read several discussions regarding
this issue, but we're yet to find a resolution.

Below is our code. Are we missing something simple or is this a quirk
in the 3.5 Framework?

Thanks in advance!

Public Class CSSTreeNode
Inherits System.Web.UI.WebControls.TreeNode

Public Sub New()
End Sub

Public Sub New(ByRef owner As System.Web.UI.WebControls.TreeView,
IsRoot As Boolean)
MyBase.New(owner, IsRoot)
End Sub

Public Sub New(ByVal text As String, ByVal value As String)
MyBase.New(text, value)
End Sub

Public Sub New(ByVal text As String, ByVal value As String, ByVal
imageURL As String)
MyBase.New(text, value, imageURL)
End Sub

Private _cssClass As String
Public Property CssClass() As String
CssClass = _cssClass
End Get
Set(ByVal value As String)
_cssClass = value
End Set
End Property

Protected Overrides Sub RenderPretext(ByVal writer As
writer.AddAttribute("class", CssClass)
End Sub

Protected Overrides Sub RenderPostText(ByVal writer As
End Sub

Protected Overrides Sub LoadViewState(ByVal state As Object)
If state IsNot Nothing Then
Dim arStates() As Object = state
CssClass = arStates(1)
End If
End Sub

Protected Overrides Function SaveViewState() As Object
Dim arStates(2) As Object
arStates(0) = MyBase.SaveViewState()
arStates(1) = CssClass
Return arStates
End Function

End Class


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