How to overide delete event a node by key Delete

I want to catch event and overide when delete a note by hot key Delete, help me please!

It depends on what you want to do. Please read http://gojs.net/latest/intro/commands.html if you want to sometimes prevent the Delete key from acting in the normal manner.

But if you want to perform additional work when a CommandHandler.deleteSelection happens, I suggest that you implement a “SelectionDeleted” DiagramEvent listener. http://gojs.net/latest/api/symbols/DiagramEvent.html