Engine中如何强制所有label都显示？

IAnnotateMap pAnnoMap = new MaplexAnnotateMapClass(); 

axMapControl1.Map.AnnotationEngine = pAnnoMap; 

IGeoFeatureLayer pGeoFeatLayer = axMapControl1.get_Layer(0) as IGeoFeatureLayer; 

IAnnotateLayerPropertiesCollection pAnnoProps = pGeoFeatLayer.AnnotationProperties; 

pAnnoProps.Clear(); 

ILabelEngineLayerProperties2 pLabelEngine2 = new MaplexLabelEngineLayerPropertiesClass(); 

pLabelEngine2.Expression = [FULL_NAME]; 



IMaplexOverposterLayerProperties pMaplexPro = new MaplexOverposterLayerPropertiesClass(); 

pMaplexPro.FeatureType = esriBasicOverposterFeatureType.esriOverposterPolygon; 

pMaplexPro.PolygonPlacementMethod = esriMaplexPolygonPlacementMethod.esriMaplexHorizontalInPolygon; 

pMaplexPro.CanPlaceLabelOutsidePolygon = false; 

pMaplexPro.CanRemoveOverlappingLabel = false; 

pMaplexPro.RepeatLabel = false; 

pLabelEngine2.OverposterLayerProperties = pMaplexPro as IOverposterLayerProperties; 

IMapOverposter pMapPos = axMapControl1.Map as IMapOverposter; 

IOverposterProperties pOP = pMapPos.OverposterProperties; 

IMaplexOverposterProperties pMaplexOP = pOP as IMaplexOverposterProperties; 

pMaplexOP.LabelLargestPolygon = false; 

pAnnoProps.Add(pLabelEngine2 as IAnnotateLayerProperties); 

pGeoFeatLayer.DisplayAnnotation = true; 

axMapControl1.ActiveView.Refresh();