AutoCAD .NET :: Stopping A Block From Being Erased

I am working on a .Net plugin and need to handle some events. The first one I'm playing with is the ability to prevent a block from being erased. My method for doing this was to add a handler to the database object of the current document, and look for blocks being erased and then check its name/attributes. I realize that the code is buggy and will only work for blocks - but it's currently just a proof of concept. I have hard-coded the block name, and set a check for if the attributes contain "123". It seems to work, but after I un-erase the blocks they don't redraw. I've gotten better results with calling .Draw on the object, but I still have to regen the drawing manually.

<CommandMethod("protectblock", CommandFlags.Session)> _ Public Sub protectblock() Dim currentDocument As Document = Autodesk.AutoCAD.ApplicationServices.Application.DocumentManager.MdiActiveDocument Dim currentDatabase As Database = currentDocument.Database AddHandler currentDatabase.ObjectErased, New ObjectErasedEventHandler(AddressOf callback_ObjectErased) End Sub 

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