Load multiple json in one diagram

is there anyway to load multiple json in one diagram whiteout loosing the previous one? coz when i use “mydiagram.model = go.Model.fromJson(JsonString)” it override my previous diagram.
Thanks in advance

You need to call Model | GoJS API (and GraphLinksModel.addLinkDataCollection).

Caution: you need to worry about duplicate keys.

Also read Replacing a single node with it's child model

Thanks man,