/// <summary>
/// 创建几何图形对应的用于高亮显示的元素
/// </summary>
/// <param name="geometry"></param>
/// <returns></returns>
private static IElement CreateHightLightElement(IGeometry geometry)
{
IElement element = null;
IColor redcolor = ColorCreate.GetIColor(255, 0, 0, 50);
IColor bluecolor = ColorCreate.GetIColor(0, 0, 255);
switch (geometry.GeometryType)
{
case esriGeometryType.esriGeometryLine:
case esriGeometryType.esriGeometryPolyline:
element = new LineElementClass();
element.Geometry = geometry;
((ILineElement)element).Symbol = SymbolCreate.GetSimpleLineSymbol(redcolor);
break;
case esriGeometryType.esriGeometryPolygon:
element = new PolygonElementClass();
element.Geometry = geometry;
((PolygonElementClass)element).Symbol = SymbolCreate.GetSimpleFillSymbol(redcolor, bluecolor);
break;
case esriGeometryType.esriGeometryPoint:
element = new MarkerElementClass();
element.Geometry = geometry;
IMarkerSymbol pisymbol = new SimpleMarkerSymbolClass();
pisymbol.Color = (IColor)redcolor;
pisymbol.Size = 6;
((MarkerElementClass)element).Symbol = pisymbol;
break;
}
return(element);
}
/// <summary>
/// 显示指定图层指定字段的标注
/// </summary>
/// <param name="geoLayer">要设置注标注的图层(IFeatureLayer as IGeoFeatureLayer)</param>
/// <param name="fieldName">显示标注的字段</param>
/// <param name="fontName">标注的字体</param>
/// <param name="size">标注的大小</param>
public static void ShowLabel(this IGeoFeatureLayer geoLayer, string fieldName, string fontName = "宋体", int size = 12)
{
//标注属性集
IAnnotateLayerPropertiesCollection annotateLyrProColl = geoLayer.AnnotationProperties;
annotateLyrProColl.Clear();
//普通标准属性（另一个是Maplex标准属性）
ILabelEngineLayerProperties labelEngine = new LabelEngineLayerPropertiesClass();
labelEngine.Expression = $"[{fieldName}]";
//字体
IFontDisp fontDisp = new StdFont()
{
Name = fontName, Bold = false
} as IFontDisp;
//标注符号
ITextSymbol textSymbol = new TextSymbolClass();
textSymbol.Color = ColorCreate.GetIColor(0, 0, 0);
textSymbol.Font = fontDisp;
textSymbol.Size = size;
labelEngine.Symbol = textSymbol;
//设置同名标注：默认为移除同名标注，应设为每个要素放置一个标注
IBasicOverposterLayerProperties basicOverpLyrPro = labelEngine.BasicOverposterLayerProperties as IBasicOverposterLayerProperties;
basicOverpLyrPro.NumLabelsOption = esriBasicNumLabelsOption.esriOneLabelPerShape;//每个要素放置一个标注
annotateLyrProColl.Add(labelEngine as IAnnotateLayerProperties);
geoLayer.DisplayAnnotation = true;
}
