TryGetVertexShape
        (
            ExcelTableReader.ExcelTableRow oRow,
            String sColumnName,
            out VertexShape eShape
        )
        {
            Debug.Assert(oRow != null);
            Debug.Assert(!String.IsNullOrEmpty(sColumnName));
            AssertValid();

            eShape = VertexShape.Circle;
            String sShape;

            if (!oRow.TryGetNonEmptyStringFromCell(sColumnName, out sShape))
            {
                return(false);
            }

            VertexShapeConverter oVertexShapeConverter =
                new VertexShapeConverter();

            if (!oVertexShapeConverter.TryWorkbookToGraph(sShape, out eShape))
            {
                OnWorkbookFormatErrorWithDropDown(oRow, sColumnName, "shape");
            }

            return(true);
        }