几何对象和空间参考

  1   //如何构建Point
  2         private IPoint ConstructPoint(double x, double y)
  3         {
  4             IPoint pPoint = new ESRI.ArcGIS.Geometry.Point();
  5             pPoint.PutCoords(x,y);
  6             return pPoint;
  7         }
  8 
  9 
 10         //如何构建MultiPoint
 11         private IGeometry GetMutipointGeometry()
 12         {
 13             const double multiPointCount = 25;
 14             IPointCollection pointCollection = new Multipoint();
 15             for (int i = 0; i < multiPointCount; i++)
 16             {
 17                 pointCollection.AddPoint(GetPoint(),Type.Missing,Type.Missing);
 18             }
 19             return pointCollection as IGeometry;
 20         }
 21         private IPoint GetPoint()
 22         { 
 23             const double min=-10;
 24             const double max=10;
 25             Random random=new Random();
 26             double x=min+(max-min)*random.NextDouble();
 27             double y = min + (max - min) * random.NextDouble();
 28             return ConstructPoint(x,y);
 29         }
 30 
 31         //Polyline的构成
 32         private IGeometry GetPolylineGeometry()
 33         {
 34             const double pathCount = 3;
 35             const double pathVetexCount = 3;
 36             IGeometryCollection pGeometryCollection = new Polyline() as IGeometryCollection;
 37             for (int i = 0; i < pathCount; i++)
 38             {
 39                 IPointCollection pointCollection = new Path();
 40                 for (int j = 0; j < pathVetexCount; j++)
 41                 {
 42                     pointCollection.AddPoint(GetPoint(),Type.Missing,Type.Missing);
 43                 }
 44                 pGeometryCollection.AddGeometry(pointCollection as IGeometry,Type.Missing,Type.Missing);
 45             }
 46             return pGeometryCollection as IGeometry;
 47         }
 48 
 49         //构造Polygon
 50         public IPolygon CreatePolygonByPoints(IPointCollection pointCollection)
 51         {
 52             IGeometryBridge2 pGeometryBridge2 = new GeometryEnvironment() as IGeometryBridge2;
 53             IPointCollection4 polygon = new Polygon() as IPointCollection4;
 54             WKSPoint[] wksPoint = new WKSPoint[pointCollection.PointCount];
 55             for (int i = 0; i < pointCollection.PointCount; i++)
 56             {
 57                 wksPoint[i].X = pointCollection.get_Point(i).X;
 58                 wksPoint[i].Y = pointCollection.get_Point(i).Y;
 59             }
 60             pGeometryBridge2.SetWKSPoints(polygon as IPointCollection4, wksPoint);
 61             IPolygon pPoly = polygon as IPolygon;
 62             pPoly.Close();
 63             return pPoly;
 64         }
 65 
 66         //通过IGeometryCollection构造Polygon对象
 67         private IPolygon ConstructorPolygon(List<IRing> ringList)
 68         {
 69             try
 70             {
 71                 IGeometryCollection pGCollection = new Polygon() as IGeometryCollection;
 72                 object o = Type.Missing;
 73                 for (int i = 0; i < ringList.Count; i++)
 74                 { 
 75                   //通过IGeometryCollection的AddGeometry方法像polygon里添加Ring对象
 76                     pGCollection.AddGeometry(ringList[i]);
 77                 }
 78                 //QI至ITopologicalOperator
 79                 ITopologicalOperator pTopoloical = pGCollection as ITopologicalOperator;
 80                 //执行Simplify操作
 81                 pTopoloical.Simplify();
 82                 IPolygon polygon = pTopoloical as IPolygon;
 83                 return polygon;
 84 
 85             }
 86             catch(Exception ex)
 87             {
 88                 return null;
 89             }            
 90         }
 91 
 92         private IPolygon MergePoilygons(IPolygon firstPolygon, IPolygon secondPolygon)
 93         {
 94             try
 95             {
 96                 //创建一个Polygon对象
 97                 IGeometryCollection pGCollection = new Polygon() as IGeometryCollection;
 98                 IGeometryCollection pGCollection1 = firstPolygon as IGeometryCollection;
 99                 IGeometryCollection pGCollection2 = secondPolygon as IGeometryCollection;
100                 pGCollection.AddGeometryCollection(pGCollection1);
101                 pGCollection.AddGeometryCollection(pGCollection2);
102                 ITopologicalOperator pTopological = pGCollection as ITopologicalOperator;
103                 pTopological.Simplify();
104                 IPolygon polygon = pTopological as IPolygon;
105                 return polygon;
106             }
107             catch (Exception ex)
108             {
109                 return null;
110             }
111         }
112 
113        //等距离打断线
114         private IEnumGeometry MakeMutiPoints(IPolyline pGeometry,int intPoints)
115         {
116             IConstructGeometryCollection pConGeoCollection = new GeometryBag() as IConstructGeometryCollection;
117             pConGeoCollection.ConstructDivideEqual(pGeometry, intPoints, esriConstructDivideEnum.esriDivideIntoPolylines);
118             IEnumGeometry pEnumGeo = pConGeoCollection as IEnumGeometry;
119             return pEnumGeo;
120         }
121         //同一基准面的坐标转换
122         private IPoint GetpProjectedPoint(IPoint pPoint, bool pBool)
123         {
124             ISpatialReferenceFactory pSpaceReferenceFactory = new SpatialReferenceEnvironment();
125             ISpatialReference pFromSpatialReference = pSpaceReferenceFactory.CreateGeographicCoordinateSystem((int)esriSRGeoCS3Type.esriSRGeoCS_Xian1980);
126             ISpatialReference pToSpatialReference = pSpaceReferenceFactory.CreateProjectedCoordinateSystem((int)esriSRProjCS4Type.esriSRProjCS_Xian1980_3_Degree_GK_Zone_34);
127             if (pBool == true)
128             {
129                 IGeometry pGeo = pPoint as IGeometry;
130                 pGeo.SpatialReference = pFromSpatialReference;
131                 pGeo.Project(pToSpatialReference);
132                 return pPoint;
133             }
134             else 
135             {
136                 IGeometry pGeo = pPoint as IPoint;
137                 pGeo.SpatialReference = pToSpatialReference;
138                 pGeo.Project(pFromSpatialReference);
139                 return pPoint;
140             }        
141         }
142         //不同基准面子之间的坐标转换
143         public void ProjectExExample()
144         {
145             ISpatialReferenceFactory pSpatialReferenceFactory = new SpatialReferenceEnvironment();
146            // ISpatialReference pFromCustom = pSpatialReferenceFactory.CreateESRISpatialReferenceFromPRJFile(@"E:1.prj");
147 
148             IPoint pFromPoint = new ESRI.ArcGIS.Geometry.Point();
149             pFromPoint.X = 518950.788;
150             pFromPoint.Y = 4335923.97;
151             IZAware pZAware = pFromPoint as IZAware;
152             pZAware.ZAware = true;
153             pFromPoint.Z = 958.4971;
154             //pFromPoint.SpatialReference = pFromCustom;
155 
156             //自定义下定的北京6度19带
157             pFromPoint.SpatialReference = CreateCustomProjectedSystem();
158 
159             //目标投影
160             IProjectedCoordinateSystem projectedCoordinateSystem = pSpatialReferenceFactory.CreateProjectedCoordinateSystem((int)esriSRProjCS4Type.esriSRProjCS_Xian1980_GK_Zone_19);
161             
162             //因为目标基准面和原始基准面不在同一个基准面上，所以牵涉参数的设置，我们用七参数转换
163             ICoordinateFrameTransformation pCoordinateFrameTransformation = new CoordinateFrameTransformation() as ICoordinateFrameTransformation;
164             pCoordinateFrameTransformation.PutParameters(-112.117,4.530,21.89,-0.00058702,-0.00476421,0.00009358,0.99998006411);
165             pCoordinateFrameTransformation.PutSpatialReferences(CreateCustomProjectedSystem(),projectedCoordinateSystem as ISpatialReference);
166 
167 
168 
169             //投影转换
170             IGeometry2 pGeometry = pFromPoint as IGeometry2;
171             pGeometry.ProjectEx(projectedCoordinateSystem ,esriTransformDirection.esriTransformForward,pCoordinateFrameTransformation,false,0,0);
172 
173 
174         }
175 
176         private IProjectedCoordinateSystem CreateCustomProjectedSystem()
177         {
178             ISpatialReferenceFactory2 pSpatialReferenceFactory = new SpatialReferenceEnvironment() as ISpatialReferenceFactory2;
179             IProjectionGEN pProjection = pSpatialReferenceFactory.CreateProjection((int)esriSRProjectionType.esriSRProjection_GaussKruger) as IProjectionGEN;
180 
181             IGeographicCoordinateSystem pGeographicCoordinateSystem = pSpatialReferenceFactory.CreateGeographicCoordinateSystem((int)esriSRGeoCSType.esriSRGeoCS_WGS1984);
182 
183             ILinearUnit pUnit = pSpatialReferenceFactory.CreateUnit((int)esriSRUnitType.esriSRUnit_Meter) as ILinearUnit;
184 
185             IParameter[] pParameter = pProjection.GetDefaultParameters();
186             IProjectedCoordinateSystemEdit pProjectedCoordinateSystemEdit = new ProjectedCoordinateSystem() as IProjectedCoordinateSystemEdit;
187 
188             object pName = "WGS-Beijing1954";
189             object pAlias = "WGS-Beijing1954";
190             object pAbbreviation = "WGS-Beijing1954";
191             object pRemarks = "WGS-Beijing1954";
192             object pUsage = "Caculate meter from lat and lon";
193             object ppGeographicCoordinateSystemObject = pGeographicCoordinateSystem ;
194             object pUnitObject = pUnit;
195             object pProjectionObject = pProjection;
196             object pParameterObject = pParameter;
197 
198             pProjectedCoordinateSystemEdit.Define(ref pName, ref pAlias, ref pAbbreviation, ref pRemarks, ref pUsage, ref ppGeographicCoordinateSystemObject, ref pUnitObject, ref pProjectionObject, ref pParameterObject);
199 
200             IProjectedCoordinateSystem5 pProjectedCoordinateSystem = pProjectedCoordinateSystemEdit as IProjectedCoordinateSystem5;
201             pProjectedCoordinateSystem.FalseEasting = 5000000;
202             pProjectedCoordinateSystem.LatitudeOfOrigin = 0;
203             pProjectedCoordinateSystem.set_CentralMeridian(true,111);
204             pProjectedCoordinateSystem.ScaleFactor = 1;
205             pProjectedCoordinateSystem.FalseNorthing = 0;
206             return pProjectedCoordinateSystem;
207         }