https://gojs.net/latest/samples/records.html
I’m new to GoJS. The example above shows how to add links between fields.
But I find a issue when I draw a link from 'field1 in ‘Record1’ to ‘fieldA’ in ‘Record2’:
I can’t draw a link from any fields in ‘Record2’ towards any fields in ‘Record1’;
2.Draw a link from any fields in ‘Record1’ towards any fields in ‘Record2’ is still available;
The sample explicitly disallows the creation of cycles in the graph represented by the diagram. It does so by setting Diagram | GoJS API.
The sample was designed for the commonplace situation of having the user define a mapping between two collections of items, so cycles and duplicate links are not permitted. If you are interested in learning more about programmatically controlling what links the user is allowed to draw, please read GoJS Validation -- Northwoods Software.