To establish dependencies between object properties, an application adds edges between graph nodes. An edge is defined by specifying a start node and an end node and specifying whether the edge is invertible. Edges are added to a graph with the AcDbEvalGraph::addEdge() function.
To obtain information about edges, applications use the getOutgoingEdges(), getIncomingEdges(), or getEdgeInfo() function of AcDbEvalGraph. These functions return one or more instances of the AcDbEvalEdgeInfo class. AcDbEvalEdgeInfo objects identify the nodes of an edge, and provide other metadata such as whether the edge is currently invertible, directed, or suppressed. See Activation Phase for information on invertible, directed, and suppressed edges.