GraphObjects can only be in <a>Node</a>s or <a>Group</a>s, not in <a>Link</a>s or <a>Adornment</a>s or simple <a>Part</a>s.
  So there is no reason to try to set <a>GraphObject.portId</a> on any object in a Link.
</p>
<p>
<p>
  See samples that make use of ports in the <a href="../samples/index.html#ports">samples index</a>.
</p>
</p>

<h2 id="SinglePorts">Single Ports</h2>
<p>
  In many situations you want to consider links logically related to the node as a whole but you don't want links
  connecting to t