Click on a port to toggle its selection. The Delete command will only delete selected ports, if there are any; otherwise it will delete Nodes and Links as it normally would.
The model data, automatically updated after each change or undo or redo:
It is sometimes useful to display a variable number of elements in a node by data binding to a JavaScript Array. In GoJS, this is simply achieved by binding (or setting) Panel.itemArray. The Panel will create an element in the panel for each value in the Array. More information can be found in the GoJS Intro.
Specific elements of a Node at which links may connect are called ports. There may be any number of ports in a node. By default there is just one port, the whole node, which results in the effect of having the whole node act as the port. Port-like GraphObjects can only be in Nodes or Groups, not in Links or Adornments or simple Parts.
More information can be found in the GoJS Intro.
The GoJS Geometry class controls the "shape" of a Shape, whereas the Shape.fill and Shape.stroke and other shape properties control the colors and appearance of the shape. For common shape figures, there are predefined geometries that can be used by setting Shape.figure. However one can also define custom geometries.
One can construct any Geometry by allocating and initializing a Geometry of at least one PathFigure holding some PathSegments. But you may find that using the string representation of a Geometry is easier to write and save in a database. Use the static method Geometry.parse or the Shape.geometryString property to transform a geometry path string into a Geometry object.
More information can be found in the GoJS Intro.