Note that the ID of an element is different from the value of its 'id' attribute.
- po:The element on which to perform the test.
- classId:The extension class ID against which to test.
- id:The element ID against which to test.
boolean ITRIGMLELEMENT_Is(ITrigmlElement* po, AEECLSID classId, uint16 id);
TRUE if the element has the given class ID and element ID. FALSE if the element has a different class ID or element ID.