IStructureddocumenttag.placeholder property. Gets the [BuildingBlock](../../../aspose.words.buildingblocks/buildingblock/) containing placeholder text which should be displayed when this SDT run contents are empty, the associated mapped XML element is empty as specified via the [IStructureddocumenttag.xml_mapping](../xml_mapping/) element or the [IStructureddocumenttag.is_showing_placeholder_text](../is_showing_placeholder_text/) element is true.... StructuredDocumentTa ( doc , aw . markup...ext builder = aw . DocumentBuilder ( doc = doc ) builder . insert_node...