开源SharpMap实例讲解(三)

1、private SharpMap.Data.FeatureDataSet QueryMapByClick(SharpMap.Geometries.Point clickPoint1, SharpMap.Geometries.Point clickPoint2) SharpMap.Data.FeatureDataSet ds = new SharpMap.Data.FeatureDataSet(); SharpMap.Geometries.BoundingBox objBounds; if (clickPoint1.X != clickPoint2.X) objBounds = new Shar

2、pMap.Geometries.BoundingBox(clickPoint1.X, clickPoint1.Y, clickPoint2.X, clickPoint2.Y); else objBounds = new SharpMap.Geometries.BoundingBox(clickPoint1.X - 0.01, clickPoint1.Y - 0.01, clickPoint1.X + 0.01, clickPoint1.Y + 0.01); . /Execute click-query on first layer in layers collection SharpMap.L

3、ayers.VectorLayer objVLyr = myMap.Layers站点站点 as SharpMap.Layers.VectorLayer; if (!objVLyr.DataSource.IsOpen) objVLyr.DataSource.Open(); objVLyr.DataSource.ExecuteIntersectionQuery(objBounds, ds); if (ds.Tables.Count 0) /We have a result return ds; for (int i = 0; i dsResult.Tables0.Columns.Count; i+

4、) lblProperty.Text += + dsResult.Tables0.Columnsi.ColumnName; lblProperty.Text += + dri.ToString() + ; lblProperty.Text += ; lblProperty.Visible = true; + QueryMapByClick函数函数private SharpMap.Data.FeatureDataSet QueryMapByClick(SharpMap.Geometries.Point clickPoint) SharpMap.Data.FeatureDataSet ds = n

5、ew SharpMap.Data.FeatureDataSet(); SharpMap.Layers.VectorLayer objVLyr = myMap.Layers0 as SharpMap.Layers.VectorLayer; if (!objVLyr.DataSource.IsOpen) objVLyr.DataSource.Open(); SharpMap.Geometries.BoundingBox objBounds = new SharpMap.Geometries.BoundingBox(clickPoint.X - 0.01, clickPoint.Y - 0.01,

6、clickPoint.X + 0.01, clickPoint.Y + 0.01); objVLyr.DataSource.ExecuteIntersectionQuery(objBounds, ds); / objVLyr.DataSource.ExecuteIntersectionQuery(clickPoint, ds); if (ds.Tables.Count 0) /We have a result /Add clicked features to a new selection layer SharpMap.Layers.VectorLayer laySelected = new

7、SharpMap.Layers.VectorLayer(Selection); laySelected.DataSource = new SharpMap.Data.Providers.GeometryProvider(ds.Tables0); laySelected.Style.Fill = new System.Drawing.SolidBrush(System.Drawing.Color.Yellow); myMap.Layers.Add(laySelected); return ds; QueryMapByClick函数函数。 laySelected.DataSource = new

8、SharpMap.Data.Providers.GeometryProvider(ds.Tables0); laySelected.Style.Fill = new System.Drawing.SolidBrush(System.Drawing.Color.Yellow); myMap.Layers.Add(laySelected); return ds; /判断字段值是否相等，若相等，则查询到该要素 if (tempFeatsFieldName.ToString() = sFieldValue) /高亮度显示该要素 SharpMap.Data.FeatureDataTable tempTa

9、ble = new SharpMap.Data.FeatureDataTable(); tempTable = (tempFeat.Table as SharpMap.Data.FeatureDataTable).Clone(); tempTable.LoadDataRow(tempFeat.ItemArray, false); FeatureDataRow tempRow; tempRow = tempTable.RowstempTable.Rows.Count - 1 as FeatureDataRow; tempRow.Geometry = tempFeat.Geometry; Shar

10、pMap.Layers.VectorLayer laySelected = new SharpMap.Layers.VectorLayer(Selection); laySelected.DataSource = new SharpMap.Data.Providers.GeometryProvider(tempTable); laySelected.Style.Fill = new System.Drawing.SolidBrush(System.Drawing.Color.Yellow); myMap.Layers.Add(laySelected); /显示该要素的其他属性 lblPrope

11、rty.Text = ; lblProperty.Text += 属性：; for (int j = 0; j tempFeat.Table.Columns.Count; j+) / lblProperty.Text += tempFeat.Table.Columnsi.ColumnName+ +tempFeati.ToString()+ lblProperty.Text += + tempFeat.Table.Columnsj.ColumnName; lblProperty.Text += + tempFeatj.ToString() + ; lblProperty.Visible = tr

12、ue; break; laySelected.Style.Fill = new System.Drawing.SolidBrush(System.Drawing.Color.Yellow); myMap.Layers.Add(laySelected); /显示该要素的其他属性 lblProperty.Text = ; lblProperty.Text += 属性：; for (int j = 0; j tempFeat.Table.Columns.Count; j+) / lblProperty.Text += tempFeat.Table.Columnsi.ColumnName+ +tempFea