标签：接口 element oev null geometry ica view get try
这里提到的空间分析（SpatialAnalysis）特指ArcEngine中使用空间筛选器（SpatialFilter）来实现的空间筛选分析，可以使用其自带的空间交互类型（如：相交、包含、相切等）进行分析，也可以使用九交模型来分析，不管使用哪种方式，这种分析都是精确的无差别的，也就是说不能设置容差的，这种分析在实际使用中是有一定的局限性的，后续的文章我们可能会讲到。同时，空间筛选器是属性筛选器的扩展和延伸，因此空间分析还具备了属性筛选的功能，这个特性很有用，可以缩小筛选范围，辅助空间分析定位。
IFeatureClass、ISpatialFilter、IQueryFilter、IFeatureCursor
1 IGraphicsContainer container = axMapControl1.ActiveView as IGraphicsContainer; 2 IGeometry geometry = axMapControl1.TrackPolygon(); 3 4 IElement element = new PolygonElementClass(); 5 element.Geometry = geometry; 6 container.AddElement(element, 0); 7 axMapControl1.Refresh(esriViewDrawPhase.esriViewGraphics, null, null); 8 Application.DoEvents(); 9 10 11 ILayer layer = this.axMapControl1.get_Layer(0); 12 IFeatureLayer featureLayer = layer as IFeatureLayer; 13 IFeatureClass featureClass = featureLayer.FeatureClass; 14 15 ISpatialFilter filter = new SpatialFilterClass(); 16 filter.Geometry = geometry; 17 filter.GeometryField = featureClass.ShapeFieldName; 18 filter.SpatialRel = esriSpatialRelEnum.esriSpatialRelIntersects; 19 20 IFeatureCursor cursor = featureClass.Search(filter, false); 21 IFeature feature = cursor.NextFeature(); 22 while (feature != null) 23 { 24 axMapControl1.FlashShape(feature.Shape); 25 26 IElement featureElement = new PolygonElementClass(); 27 featureElement.Geometry = feature.Shape; 28 container.AddElement(featureElement, 99); 29 30 feature = cursor.NextFeature(); 31 } 32 33 axMapControl1.Refresh(esriViewDrawPhase.esriViewGraphics, null, null); 34 System.Runtime.InteropServices.Marshal.ReleaseComObject(cursor);
标签：接口 element oev null geometry ica view get try
原文地址：https://www.cnblogs.com/HelsingWang/p/8946672.html
