' PropertyValueUIHandler delegate that provides PropertyValueUIItem
' objects to any properties named HorizontalMargin or VerticalMargin.
Private Sub marginPropertyValueUIHandler(ByVal context As System.ComponentModel.ITypeDescriptorContext, ByVal propDesc As System.ComponentModel.PropertyDescriptor, ByVal itemList As ArrayList)
    ' A PropertyValueUIHandler added to the IPropertyValueUIService
    ' is queried once for each property of a component and passed
    ' a PropertyDescriptor that represents the characteristics of 
    ' the property when the Properties window is set to a new 
    ' component. A PropertyValueUIHandler can determine whether 
    ' to add a PropertyValueUIItem for the object to its ValueUIItem 
    ' list depending on the values of the PropertyDescriptor.
    If propDesc.DisplayName.Equals("HorizontalMargin") Then
        Dim img As Image = DeserializeFromBase64Text(imageBlob1)
        itemList.Add(New PropertyValueUIItem(img, New PropertyValueUIItemInvokeHandler(AddressOf Me.marginInvoke), "Test ToolTip"))
    End If
    If propDesc.DisplayName.Equals("VerticalMargin") Then
        Dim img As Image = DeserializeFromBase64Text(imageBlob1)
        img.RotateFlip(RotateFlipType.Rotate90FlipNone)
        itemList.Add(New PropertyValueUIItem(img, New PropertyValueUIItemInvokeHandler(AddressOf Me.marginInvoke), "Test ToolTip"))
    End If
End Sub