How can I check whether a node being removed or added is a temporary node inside the modelchanged event on the diagrammodel? I know the node class has an istemporary property, but the data class, which is derived from GraphLinksModelNodeData does not seem to have anything of the sort.
There’s no requirement upon the programmer that their model data have to include any particular information in it. Particularly not with any state that is inherently so transient. (As an extreme example, you could use integers as your node data type.)
But you could look at the DiagramModel.SkipsUndoManager property to get the clue that it’s a transient change.
By the way, it isn’t Node or Part that has an IsTemporary property: it’s Layer.
DiagramModel.SkipsUndoManager is what I wanted. Thanks Walter.