Button to zoom diagram

Okay I would see the examples of backups, I would like to add a button for example allowing me to zoom and zoom the graph if necessary. For indexes, my links are numbered
I would like to add a clue to differentiate two links of the same number. thank you very much

I split this off from the other topic since it’s unrelated to saving/loading. Please try to put new topics in their own thread.

For buttons that zoom, you could either use something like a zoom to fit button (see the Family Tree sample), or buttons that change the Diagram.scale. You may also be interested in this topic, which discusses using the CommandHandler for zooming: Zoom In / Zoom out is not working.

I don’t know what you mean about numbered links, can you provide an example?

Thank you for your help I will try to see the links you gave me.
For the links I want to assign them numbers.
For example 1 for the first one that will incrust each new link create.

If you are using a GraphLinksModel, then you can add whatever properties you want to each link data object in the GraphLinksModel.linkDataArray.

You can show that number or any other information in a text label that is part of the Link. Read about this at GoJS Link Labels -- Northwoods Software.