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查询矩形范围内的"点"要素

查询 quot 范围 矩形 要素
2023-09-27 14:28:06 时间

步骤

  1,首先在含有主视图控件 ESRI.ArcGIS.Controls.AxMapControl mapCtrl_main 的主类中定义一个 IEnvelope 成员变量,用于记录鼠标在主视图控件画好的轮廓

1 private ESRI.ArcGIS.Geometry.IEnvelope mainInvelope = null; //(主视图上)
2 public ESRI.ArcGIS.Geometry.IEnvelope MainInvelopeValue {
3     get {
4     return mainInvelope;
5     }
6 }

并设置成外界可访问的属性.

  2,在该类中定义一bool变量,以控制查询

1 private bool startMainInvelope = false; //标识在主视图上画轮廓矩形,以进行该范围内点查询.

  3,在 mapCtrl_main 的 OnMouseDown 响应事件中,控制轮廓的顺畅画好

 1 if (1 == e.button && startMainInvelope) {   //在主视图上画轮廓.
 2     mainInvelope = mapCtrl_main.TrackRectangle();
 3     try {
 4         if (!mainInvelope.IsEmpty)
 5         Engine.App_Code.Draw.DrawSymbol(mapCtrl_main.Map, mainInvelope);
 6     }
 7     catch (System.Exception ex) {
 8         MessageBox.Show(ex.Message);
 9     }
10 }

其中用到画轮廓的辅助方法定义为:

 1 /// <summary>
 2         /// 画轮廓.
 3         /// </summary>
 4         /// <param name="sender"></param>
 5         /// <param name="e">根据IEnvelope对象画轮廓.</param>
 6         public static void DrawSymbol(ESRI.ArcGIS.Carto.IMap map, ESRI.ArcGIS.Geometry.IEnvelope e) {
 7             ESRI.ArcGIS.Carto.IGraphicsContainer hawkGC = (ESRI.ArcGIS.Carto.IGraphicsContainer)map;
 8             ESRI.ArcGIS.Carto.IActiveView aView = (ESRI.ArcGIS.Carto.IActiveView)hawkGC;
 9             hawkGC.DeleteAllElements();
10 
11             ESRI.ArcGIS.Carto.IElement recEle = (ESRI.ArcGIS.Carto.IElement)new ESRI.ArcGIS.Carto.RectangleElementClass();
12             recEle.Geometry = e;
13             ESRI.ArcGIS.Display.ISimpleLineSymbol outLine = new ESRI.ArcGIS.Display.SimpleLineSymbolClass();
14             outLine.Color = ColorPaint(255, 255);
15             outLine.Width = 2;
16 
17             //填充样式.
18             ESRI.ArcGIS.Display.ISimpleFillSymbol fillSym = new ESRI.ArcGIS.Display.SimpleFillSymbolClass();
19             fillSym.Color = ColorPaint(255, 0);
20             fillSym.Outline = outLine;
21 
22             ESRI.ArcGIS.Carto.IFillShapeElement fillShape = (ESRI.ArcGIS.Carto.IFillShapeElement)recEle;
23             fillShape.Symbol = fillSym;
24             hawkGC.AddElement((ESRI.ArcGIS.Carto.IElement)fillShape, 0);
25             aView.PartialRefresh(ESRI.ArcGIS.Carto.esriViewDrawPhase.esriViewGraphics, null, null);
26         }

  4,在查询窗口中,用 GetLayerByName 方法定位好待查询的点要素图层(方法定义为)

 1 /// <summary>
 2         /// 根据图层名获取图层.
 3         /// </summary>
 4         /// <param name="map"></param>
 5         /// <param name="layerName">图层名称.</param>
 6         /// <returns></returns>
 7         public static ESRI.ArcGIS.Carto.ILayer GetLayerByName(ESRI.ArcGIS.Carto.IMap map, string layerName) {
 8             ESRI.ArcGIS.Carto.IEnumLayer enunLayer = map.get_Layers(null, false);
 9             enunLayer.Reset();
10             ESRI.ArcGIS.Carto.ILayer resultLayer = null;
11             while ((resultLayer = enunLayer.Next()) != null) {
12                 if (resultLayer.Name.Equals(layerName)) {
13                     break;
14                 }
15             }
16             return resultLayer;
17         }

  5,查询窗口实现查询的所有代码:

 1 using System;
 2 using System.Collections.Generic;
 3 using System.ComponentModel;
 4 using System.Data;
 5 using System.Drawing;
 6 using System.Linq;
 7 using System.Text;
 8 using System.Windows.Forms;
 9 
10 namespace Engine {
11     public partial class fQueryInvelopePoints : Form {
12         private ESRI.ArcGIS.Carto.IMap map = null;
13         private fMain fMain = null;
14         public fQueryInvelopePoints(fMain fMain, ESRI.ArcGIS.Carto.IMap map) {
15             this.fMain = fMain;
16             this.map = map;
17             InitializeComponent();
18         }
19 
20         /// <summary>
21         /// 查询指定矩形范围内的点要素.
22         /// </summary>
23         /// <param name="envelope">指定的矩形范围.</param>
24         /// <param name="featureClass">待查询的要素.</param>
25         /// <returns>返回结果的游标</returns>
26         public ESRI.ArcGIS.Geodatabase.IFeatureCursor GetAllFeaturesFromPointSearchInGeoFeatureLayer(ESRI.ArcGIS.Geometry.IEnvelope envelope, ESRI.ArcGIS.Geodatabase.IFeatureClass featureClass) {
27             if (featureClass == null)
28                 return null;
29             ESRI.ArcGIS.Geodatabase.ISpatialFilter spatialFilter = new ESRI.ArcGIS.Geodatabase.SpatialFilterClass();
30             spatialFilter.Geometry = envelope;
31             spatialFilter.SpatialRel = ESRI.ArcGIS.Geodatabase.esriSpatialRelEnum.esriSpatialRelEnvelopeIntersects;
32             spatialFilter.GeometryField = featureClass.ShapeFieldName;
33             return featureClass.Search(spatialFilter, false);
34         }
35 
36         private void fQueryInvelopePoints_Load(object sender, EventArgs e) {
37             Engine.App_Code.Layer_Assist.InitLayers(map, cbox_layer);
38         }
39 
40         private void btn_query_Click(object sender, EventArgs e) {
41             lsbox.Items.Clear();    //清空原始数据.
42             ESRI.ArcGIS.Carto.ILayer lyr = Engine.App_Code.Layer_Assist.GetLayerByName(map, cbox_layer.Text);
43             if (lyr is ESRI.ArcGIS.Carto.IFeatureLayer) {   //矢量数据.
44                 ESRI.ArcGIS.Carto.IFeatureLayer fLyr = (ESRI.ArcGIS.Carto.IFeatureLayer)lyr;
45                 ESRI.ArcGIS.Geometry.IEnvelope selEnvelope = fMain.MainInvelopeValue;
46                 //获取矩形范围内的要素.
47                 ESRI.ArcGIS.Geodatabase.IFeatureCursor fCur = GetAllFeaturesFromPointSearchInGeoFeatureLayer(selEnvelope, fLyr.FeatureClass);
48                 ESRI.ArcGIS.Geodatabase.IFeatureClass fc = fLyr.FeatureClass;
49                 ESRI.ArcGIS.Geodatabase.IFeature f = null;
50                 string v = "";
51                 string k = "";
52                 k = "name";
53                 fMain.mapCtrl_main.ActiveView.Refresh();    //高亮显示前.
54                 try {
55                     while ((f = fCur.NextFeature()) != null) {
56                         map.SelectFeature(fLyr, f); //高亮显示.
57                         v = Convert.ToString(f.get_Value(f.Fields.FindField("name")));
58                         lsbox.Items.Add(k + " : " + v);
59                     }
60                 }
61                 catch (System.Exception ex) {
62                     MessageBox.Show(ex.Message + "不支持查询的图层或查询字段错误:NAME");
63                 }
64                 fMain.mapCtrl_main.ActiveView.Refresh();    //高亮显示后.
65             }
66         }
67     }
68 }

  6,运行时,画好矩形轮廓后,在主视图控件类中调用即可:

 1 if (mainInvelope == null || mainInvelope.IsEmpty) {
 2     MessageBox.Show("画轮廓为空");
 3     return;
 4 }
 5 if (fInvelopePoints == null)
 6     fInvelopePoints = new fQueryInvelopePoints(this, mapCtrl_main.Map);
 7 fInvelopePoints.FormClosed += (s, ea) => {
 8     fInvelopePoints = null;
 9 };
10 fInvelopePoints.Show(this);

其中 fInvelopePoints 为定义在主视图类中的查询窗口的成员变量:

1 //查询窗口.
2 private fQueryInvelopePoints fInvelopePoints = null;

 

  在主视图中画矩形轮廓如图:

  查询后,弹出查询结果如图: