Code

// refering diagram
        Diagram diagramPB = diagramView.Diagram;

 // delete / remove current link if its associated with a stage/lane

            // iterate through lanes/stages
            for (int i = 1; i <= extVarStages; i++)
            {
                // reference current node (lane/stage) to compare with
                ShapeNode currShapeNode = diagramPB.FindNodeById("Stage " + i) as ShapeNode;

                // check if current links' origin or destination node is any stage/lane
                if (e.Link.Origin == currShapeNode | e.Link.Destination == currShapeNode)
                {

                    // get index of current link
                    int indexOfCurrLink = diagramPB.Links.IndexOf(e.Link);

                    // if current link exists
                    if (diagramPB.Links.GetAt(indexOfCurrLink) != null)
                    {
                        // remove link from diagram at position specified by index of current link
                        diagramPB.Links.RemoveAt(indexOfCurrLink);

                        // refresh page while maintaining URL with any querystrings
                        Response.Redirect(Request.RawUrl);
                    }
                }

            }