Info tool

Info tool 
Tags: General Topics

moradoxy Mar 7 2007 at 10:29 AM	Hi every body: Some body knows how to do a info tool, this tool get all the data from all the objects on the map under a point. I´m using this code but I don´t know how to get the data: ------------------------------------------------------------------------------------------------------------------------- public string GetInfo(Map pmapMap, SharpMap.Geometries.Point ppntPoint) { string strResult=""; try { SharpMap.Layers.VectorLayer lyrMyLayer; SharpMap.Data.FeatureDataSet fds = new SharpMap.Data.FeatureDataSet(); lyrMyLayer = (SharpMap.Layers.VectorLayer)pmapMap.Layers 0; lyrMyLayer.DataSource.Open(); SharpMap.Geometries.Point pntPoint2=new SharpMap.Geometries.Point(ppntPoint.X + 1,ppntPoint.Y + 1); SharpMap.Geometries.BoundingBox bubBoundingBox = new SharpMap.Geometries.BoundingBox(ppntPoint, pntPoint2); lyrMyLayer.DataSource.ExecuteIntersectionQuery(bubBoundingBox, fds); if (fds.Tables.Count > 0) { strResult = fds.Tables 0.Rows 0.ItemArray.GetValue(0).ToString(); foreach (SharpMap.Data.FeatureDataRow feature in fds.Tables 0) { strResult = feature 0.ToString(); } ----------------------------------------------------------------------------------------------------------- this sample raise me an error when i try to get the data from the objects.
codekaizen Coordinator Mar 14 2007 at 7:42 AM	What type of Exception do you get? This would mean a lot in terms of what is going wrong. Just by looking at it, I wonder if you have an empty result set, so your fds.Tables 0.Rows 0.ItemArray is throwing a NullReferenceException.
moradoxy Mar 14 2007 at 8:15 AM	Hi: Thanks by your help, but fortunally I founded my error, and now I have the next code for get all the atributes from a layer in a specific point. There are two methods one search on the layer and the other get all the atributes from this layer and returns the data in to a array. /// <summary> /// This method get the info on only one layer under the point /// </summary> /// <param name="pmapMap">The map</param> /// <param name="ppntPoint">The point under we are goig to try search</param> /// <param name="intPositionLayer">The position of the layer in the map, zero is the initial position</param> /// <param name="pdblFactor">The factor is the distance between the points 1 and 2 that form the bounding box</param> /// <returns></returns> private ArrayList GetInfoFeatures(Map pmapMap, SharpMap.Geometries.Point ppntPoint, int intPositionLayer, double pdblFactor) { ArrayList arlResult = new ArrayList(); try { SharpMap.Layers.VectorLayer lyrMyLayer = _LayerTools.getVectorLayer(pmapMap, intPositionLayer);//get the layer SharpMap.Data.FeatureDataSet fds = new SharpMap.Data.FeatureDataSet();//Where the features will be stored SharpMap.Geometries.Point pntPoint2 = new SharpMap.Geometries.Point(ppntPoint.X + pdblFactor, ppntPoint.Y + pdblFactor);//The second point in the square SharpMap.Geometries.BoundingBox bubBoundingBox = new SharpMap.Geometries.BoundingBox(ppntPoint, pntPoint2);//Doing the area to search lyrMyLayer.DataSource.ExecuteIntersectionQuery(bubBoundingBox, fds);//Seaching the features under the square if (fds.Tables.Count > 0)//If al least one feature where founded { foreach (SharpMap.Data.FeatureDataRow feature in fds.Tables 0)//Getting all the features { arlResult.Add(GetInfoFeature(feature)); //Getting all the data from one by one feature, the column name and the value } } } catch (Exception Ex) { return null; } return arlResult; } /// <summary> /// This method return all the data of the feature, the column name and the value /// </summary> /// <param name="feature">The feature that was founded under the point</param> /// <returns></returns> private ArrayList GetInfoFeature(SharpMap.Data.FeatureDataRow feature) { ArrayList arlResult = new ArrayList(); try { foreach (System.Data.DataColumn ColColumn in feature.Table.Columns) { ArrayList arlDataColumn =new ArrayList();//A new array list arlDataColumn.Add(ColColumn.ColumnName);//The column name arlDataColumn.Add(feature ColColumn.ColumnName.ToString()); //The value of the column arlResult.Add(arlDataColumn); //The data of the column } return arlResult;//All the data of the feature } catch (Exception Ex) { return null; } return arlResult;