地图标注：是表示制图对象的名称或数量及质量特征的文字和数字等文字语言。来说明制图对象的名称、种类、性质、和数量等具体特征。
ArcEngine中注记分为两种：标注（Label）、注记（Annotation）。Annotation以更复杂的方法和属性对要素图层进行标注，这个过程可以是自动的，不需用户干预，而且注记内容可以保存到地图数据库中。
AnnotationLayerPropertiesCollection对象是一个要素图层的属性，是一个标注集对象的集合。标注集是与某个要素图层相关联的，用于描述要素图层如何被标注，可以通过IGeoFeaturelayer中的AnnotationProperties属性获取。IAnnotationLayerPropertiesCollection接口提供了对保存在集合中的IAnnocationLayerProperties（LabelEngineLayerProperties、MaplexLabelEngineProperties）对象进行操作，通过该接口，开发者可以对集合中的组件进行添加、删除、排序和查询等操作。L abelEngineLayerProperties对象维持着一个要素图层的注记实例。
IAnnocationLayerProperties的WhereClause属性用于设置一个SQL语句，确定哪些要素可以被标注。
AnnotationMaximunScale和AnnotationMinMunScale用于设置文字标注的最大和最小范围。
LabelEngineLayerProperties对象也实现ILabelEngineLayerProperties接口，提供用于制作过程中的主要属性，设置文字符号、标注文字排放等，其中BasicOverposterLayerProperties用于设置标注文本如何被放置，以及处理文字之间的冲突。IBasicOverposterLayerProperties接口中的LineLabelPlacementPriorities用于设置标注文本的摆放路径的权重，LineLabelPosition用于设置标注文本的排放位置，PointPlacementPriorities用于设置一个与点相关的标注路径的权重等。
class MapMarker { private AxMapControl axMapControl; public MapMarker(AxMapControl _axMapControl) { axMapControl = _axMapControl; } /// <summary> /// 使用注记 /// </summary> /// <param name="pGeoFeatureLyr">要注记的图层</param> /// <param name="AnnoField">注记内容</param> public void Annotation(IGeoFeatureLayer pGeoFeatureLyr, string AnnoField) { IGeoFeatureLayer pGeoFeatureLayer;//用 GeoFeatureLayer才能操作标注 pGeoFeatureLayer = pGeoFeatureLyr; IAnnotateLayerPropertiesCollection pAnnoProps;//定义标注集对象的集合 pAnnoProps = pGeoFeatureLyr.AnnotationProperties; pAnnoProps.Clear();//清除里面的集合，不知道是不是必须的 IAnnotateLayerProperties pAnnoLayerPros; ILineLabelPosition pPosition;//控制Label相对位置 ILineLabelPlacementPriorities pPlacement;//control placement position priorities for line labels IBasicOverposterLayerProperties pBasic;//Provides access to members that control the placement of labels relative to features using conflict detection ILabelEngineLayerProperties pLabelEngine;//可以控制标注的过程中的主要属性，设置文字符号，标注文字排放等 ITextSymbol pTextSymbol; pTextSymbol = new TextSymbolClass(); stdole.StdFont pFont;//定义字体吧，不知道 pFont = new stdole.StdFontClass(); pFont.Name = "Verdana"; pFont.Size = 10; pTextSymbol.Font = pFont as stdole.IFontDisp ; pTextSymbol.Color = HsvColor(250,160,200); pPosition = new LineLabelPositionClass(); pPosition.Parallel = false;//Label和线平行 pPosition.Perpendicular = true;//Label和线垂直 pPlacement = new LineLabelPlacementPrioritiesClass(); pBasic = new BasicOverposterLayerPropertiesClass(); pBasic.FeatureType = esriBasicOverposterFeatureType.esriOverposterPolyline; pBasic.LineLabelPlacementPriorities = pPlacement; pBasic.LineLabelPosition = pPosition; pLabelEngine = new LabelEngineLayerPropertiesClass(); pLabelEngine.Symbol = pTextSymbol; pLabelEngine.BasicOverposterLayerProperties = pBasic; pLabelEngine.Expression = AnnoField;//注记的内容 pAnnoLayerPros = pLabelEngine as IAnnotateLayerProperties; pAnnoProps.Add(pAnnoLayerPros); pGeoFeatureLayer.DisplayAnnotation = true; axMapControl .Refresh (esriViewDrawPhase .esriViewBackground ,null ,null ); } private HsvColor HsvColor(int hue, int saturation, int val) { HsvColor hsvColor; hsvColor = new HsvColorClass(); hsvColor.Hue = hue; hsvColor.Saturation = saturation; hsvColor.Value = val; return hsvColor; } }
示例代码
示例1
Maplex类型标注是AE标注的其中一种方式，现提供一简单使用例子 . 转自：LINK
/// <summary> /// MaplexEngine标注 /// </summary> /// <param name="pGeoFeatLyr">标注图层</param> /// <param name="pMap">地球人都知</param> /// <param name="annoField">标记字段</param> public void Annotation(IGeoFeatureLayer pGeoFeatLyr, IMap pMap, string annoField) { //如果Map没有用Maplex引擎，要先设置Map使用这个引擎 //IAnnotateMap pAnnotateMap; //pAnnotateMap = new MaplexAnnotateMapClass(); //pMap.AnnotationEngine = pAnnotateMap; IAnnotateMap pAnnoMap; pAnnoMap = new MaplexAnnotateMapClass(); pMap.AnnotationEngine = pAnnoMap; IGeoFeatureLayer pGeoFeatLayer; pGeoFeatLayer = pGeoFeatLyr; IAnnotateLayerPropertiesCollection pAnnoProps; pAnnoProps = pGeoFeatLyr.AnnotationProperties; pAnnoProps.Clear(); ILabelEngineLayerProperties2 pLabelEngine2 = new MaplexLabelEngineLayerPropertiesClass(); pLabelEngine2.Expression = "[" + annoField + "]"; 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); pGeoFeatLyr.DisplayAnnotation = true; }
示例2， LINK
public void EnableFeatureLayerLabel(IFeatureLayer pFeaturelayer, string sLableField, IRgbColor pRGB, int size, string angleField) { //判断图层是否为空 if (pFeaturelayer == null) return; IGeoFeatureLayer pGeoFeaturelayer = (IGeoFeatureLayer)pFeaturelayer; IAnnotateLayerPropertiesCollection pAnnoLayerPropsCollection; pAnnoLayerPropsCollection = pGeoFeaturelayer.AnnotationProperties; pAnnoLayerPropsCollection.Clear(); //stdole.IFontDisp pFont; //字体 ITextSymbol pTextSymbol; //pFont.Name = "新宋体"; //pFont.Size = 9; //未指定字体颜色则默认为黑色 if (pRGB == null) { pRGB = new RgbColorClass(); pRGB.Red = 0; pRGB.Green = 0; pRGB.Blue = 0; } pTextSymbol = new TextSymbolClass(); pTextSymbol.Color = (IColor)pRGB; pTextSymbol.Size = size; //标注大小 IBasicOverposterLayerProperties4 pBasicOverposterlayerProps4 = new BasicOverposterLayerPropertiesClass(); switch (pFeaturelayer.FeatureClass.ShapeType)//判断图层类型 { case ESRI.ArcGIS.Geometry.esriGeometryType.esriGeometryPolygon: pBasicOverposterlayerProps4.FeatureType = esriBasicOverposterFeatureType.esriOverposterPolygon; break; case ESRI.ArcGIS.Geometry.esriGeometryType.esriGeometryPoint: pBasicOverposterlayerProps4.FeatureType = esriBasicOverposterFeatureType.esriOverposterPoint; break; case ESRI.ArcGIS.Geometry.esriGeometryType.esriGeometryPolyline: pBasicOverposterlayerProps4.FeatureType = esriBasicOverposterFeatureType.esriOverposterPolyline; break; } pBasicOverposterlayerProps4.PointPlacementMethod = esriOverposterPointPlacementMethod.esriRotationField; pBasicOverposterlayerProps4.RotationField = angleField; ILabelEngineLayerProperties pLabelEnginelayerProps = new LabelEngineLayerPropertiesClass(); pLabelEnginelayerProps.Expression = "[" + sLableField + "]"; pLabelEnginelayerProps.Symbol = pTextSymbol; pLabelEnginelayerProps.BasicOverposterLayerProperties = pBasicOverposterlayerProps4 as IBasicOverposterLayerProperties; pAnnoLayerPropsCollection.Add((IAnnotateLayerProperties)pLabelEnginelayerProps); pGeoFeaturelayer.DisplayAnnotation = true;//很重要，必须设置 //axMapControl1.ActiveView.PartialRefresh(esriViewDrawPhase.esriViewBackground, null, null); } }
参考文章
