Question

arcgis engine C# 开发，如何实现计算点到面距离的计算？谢谢~

给定一个经纬度的点 和一个区域面文件，计算距离~

Answer 1

在AE中这叫点选查询，其中你可以用你自己的坐标来替换 下面的
IMap pMap = axMapControl1.Map;
IActiveView pActiveView = pMap as IActiveView;
IFeatureLayer pFeatureLayer = pMap.get_Layer(0) as IFeatureLayer;
IFeatureClass pFeatureClass = pFeatureLayer.FeatureClass;

//设置点击点的位置
IPoint point = pActiveView.ScreenDisplay.DisplayTransformation.ToMapPoint(e.x, e.y);
ITopologicalOperator pTOpo = point as ITopologicalOperator;
double length;
length = ConvertPixelsToMapUnits(pActiveView, 4);
IGeometry pBuffer = pTOpo.Buffer(length);
IGeometry pGeomentry = pBuffer.Envelope;
//空间滤过器
ISpatialFilter pSpatialFilter = new SpatialFilter();
pSpatialFilter.Geometry = pGeomentry;
//根据被选择要素的不同，设置不同的空间滤过关系
switch (pFeatureClass.ShapeType)
{
case esriGeometryType.esriGeometryPoint:
pSpatialFilter.SpatialRel = esriSpatialRelEnum.esriSpatialRelContains;
break;
case esriGeometryType.esriGeometryPolyline:
pSpatialFilter.SpatialRel = esriSpatialRelEnum.esriSpatialRelCrosses;
break;
case esriGeometryType.esriGeometryPolygon:
pSpatialFilter.SpatialRel = esriSpatialRelEnum.esriSpatialRelIntersects;
break;

}
IFeatureSelection pFSelection = pFeatureLayer as IFeatureSelection;
pFSelection.SelectFeatures(pSpatialFilter, esriSelectionResultEnum.esriSelectionResultNew, false);
ISelectionSet pSelectionset = pFSelection.SelectionSet;
ICursor pCursor;
pSelectionset.Search(null, true, out pCursor);
IFeatureCursor pFeatCursor = pCursor as IFeatureCursor;
IFeature pFeature = pFeatCursor.NextFeature();
while (pFeature != null)
{
pMap.SelectFeature(pFeatureLayer, pFeature);
pFeature = pFeatCursor.NextFeature();
pFeture.get_value("");//在这里你可以写上想要获取的属性的字段
}
pActiveView.PartialRefresh(esriViewDrawPhase.esriViewGraphicSelection, null, null);

上述的自定义函数是将距离的转换

private double ConvertPixelsToMapUnits(IActiveView pActiveView, double pixelUnits)
{
// Uses the ratio of the size of the map in pixels to map units to do the conversion
IPoint p1 = pActiveView.ScreenDisplay.DisplayTransformation.VisibleBounds.UpperLeft;
IPoint p2 = pActiveView.ScreenDisplay.DisplayTransformation.VisibleBounds.UpperRight;
int x1, x2, y1, y2;
pActiveView.ScreenDisplay.DisplayTransformation.FromMapPoint(p1, out x1, out y1);
pActiveView.ScreenDisplay.DisplayTransformation.FromMapPoint(p2, out x2, out y2);
double pixelExtent = x2 - x1;
double realWorldDisplayExtent = pActiveView.ScreenDisplay.DisplayTransformation.VisibleBounds.Width;
double sizeOfOnePixel = realWorldDisplayExtent / pixelExtent;
return pixelUnits * sizeOfOnePixel;
}

追问

这个不是把 没有算距离的