ArcEngine 地圖導航 查找路徑 經緯度座標導航 最優路徑分析

本文來自CSDN博客，轉載請標明出處 http//blog.csdn.net/zdb330906531

需求：根據經緯度座標，取得兩個起點與終點，顯示最優路徑實現導航。

參考官方例子後，我在arcMap上已實現效果，要求改爲代碼實現。

實現思路：1、創建路徑 2、添加位置 3、求解

代碼如下：

①    創建路徑

public INAContext CreateSolverContext(INetworkDataset networkDataset)
{
    IDENetworkDataset deNDS = GetDENetworkDataset(networkDataset);
    INASolver naSolver = new NARouteSolver();//路徑（NAClosestFacilitySolver 最近設施）
    INAContextEdit contextEdit = naSolver.CreateContext(deNDS, naSolver.Name) as INAContextEdit;
    contextEdit.Bind(networkDataset, new GPMessagesClass());
    return contextEdit as INAContext;
}
public IDENetworkDataset GetDENetworkDataset(INetworkDataset networkDataset)
{
    IDatasetComponent dsComponent = networkDataset as IDatasetComponent;
    return dsComponent.DataElement as IDENetworkDataset;
}

調用方法：

ILayer ilayer = MapLayerHelper.GetLayerByName(axMapControl1.Map, "道路_ND");
INetworkDataset networkDataset = (ilayer as INetworkLayer).NetworkDataset;//網絡數據集
INAContext m_NAContext = CreateSolverContext(networkDataset);

②    添加位置

/// <summary>
/// 在內存中創建圖層
/// </summary>
/// <param name="DataSetName">數據集名稱（所建圖層名稱）</param>
/// <param name="AliaseName">別名</param>
/// <param name="SpatialRef">空間參考</param>
/// <param name="GeometryType">幾何類型</param>
/// <param name="PropertyFields">屬性字段集合</param>
/// <returns>IfeatureLayer</returns>
public static IFeatureLayer CreateFeatureLayerInMemeory(string DataSetName, string AliaseName, ISpatialReference SpatialRef, esriGeometryType GeometryType, IFields PropertyFields)
{
    ESRI.ArcGIS.Geodatabase.IWorkspaceFactory workspaceFactory = new ESRI.ArcGIS.DataSourcesGDB.InMemoryWorkspaceFactoryClass();
    ESRI.ArcGIS.Geodatabase.IWorkspaceName workspaceName = workspaceFactory.Create("", "MyWorkspace", null, 0);
    ESRI.ArcGIS.esriSystem.IName name = (IName)workspaceName;
    ESRI.ArcGIS.Geodatabase.IWorkspace inmemWor = (IWorkspace)name.Open();
    IField oField = new FieldClass();
    IFields oFields = new FieldsClass();
    IFieldsEdit oFieldsEdit = null;
    IFieldEdit oFieldEdit = null;
    IFeatureClass oFeatureClass = null;
    IFeatureLayer oFeatureLayer = null;
    try
    {
        oFieldsEdit = oFields as IFieldsEdit;
        oFieldEdit = oField as IFieldEdit;
        if (PropertyFields != null)
        {
            for (int i = 0; i < PropertyFields.FieldCount; i++)
            {
                oFieldsEdit.AddField(PropertyFields.get_Field(i));
            }
        }
        IGeometryDef geometryDef = new GeometryDefClass();
        IGeometryDefEdit geometryDefEdit = (IGeometryDefEdit)geometryDef;
        geometryDefEdit.AvgNumPoints_2 = 5;
        geometryDefEdit.GeometryType_2 = GeometryType;
        geometryDefEdit.GridCount_2 = 1;
        geometryDefEdit.HasM_2 = false;
        geometryDefEdit.HasZ_2 = false;
        geometryDefEdit.SpatialReference_2 = SpatialRef;

        oFieldEdit.Name_2 = "SHAPE";
        oFieldEdit.Type_2 = esriFieldType.esriFieldTypeGeometry;
        oFieldEdit.GeometryDef_2 = geometryDef;
        oFieldEdit.IsNullable_2 = true;
        oFieldEdit.Required_2 = true;
        oFieldsEdit.AddField(oField);

        oFeatureClass = (inmemWor as IFeatureWorkspace).CreateFeatureClass(DataSetName, oFields, null, null, esriFeatureType.esriFTSimple, "SHAPE", "");
        (oFeatureClass as IDataset).BrowseName = DataSetName;

        oFeatureLayer = new FeatureLayerClass();
        oFeatureLayer.Name = AliaseName;
        oFeatureLayer.FeatureClass = oFeatureClass;
    }
    catch
    {}
    finally
    {
        System.Runtime.InteropServices.Marshal.ReleaseComObject(oField);
        System.Runtime.InteropServices.Marshal.ReleaseComObject(oFields);
        System.Runtime.InteropServices.Marshal.ReleaseComObject(oFieldsEdit);
        System.Runtime.InteropServices.Marshal.ReleaseComObject(oFieldEdit);
        System.Runtime.InteropServices.Marshal.ReleaseComObject(name);
        System.Runtime.InteropServices.Marshal.ReleaseComObject(workspaceFactory);
        System.Runtime.InteropServices.Marshal.ReleaseComObject(workspaceName);
        System.Runtime.InteropServices.Marshal.ReleaseComObject(inmemWor);
        System.Runtime.InteropServices.Marshal.ReleaseComObject(oFeatureClass);
        GC.Collect();
    }
    return oFeatureLayer;
}

INAClassLoader classLoader = new NAClassLoader();
classLoader.Locator = m_NAContext.Locator;
classLoader.Locator.SnapTolerance = 100;
classLoader.NAClass = m_NAContext.NAClasses.get_ItemByName("Stops") as INAClass;
//添加起點與終點位置
string[] startCoordinate = textBox1.Text.Split(',');
string[] endCoordinate = textBox2.Text.Split(',');
double x1 = SpatialReferenceHelper.ConvertDegreesToDigital(startCoordinate[0]);
double y1 = SpatialReferenceHelper.ConvertDegreesToDigital(startCoordinate[1]);
double x2 = SpatialReferenceHelper.ConvertDegreesToDigital(endCoordinate[0]);
double y2 = SpatialReferenceHelper.ConvertDegreesToDigital(endCoordinate[1]);
IPoint startPoint = new PointClass();
startPoint.PutCoords(x1, y1);
startPoint.SpatialReference = LocateHelper.GeoCoordinateSystem;
startPoint.Project(mainForm.MapForm.axMapControl1.SpatialReference);
IPoint endPoint = new PointClass();
endPoint.PutCoords(x2, y2);
endPoint.SpatialReference = LocateHelper.GeoCoordinateSystem;
endPoint.Project(mainForm.MapForm.axMapControl1.SpatialReference);

IFeatureLayer featurelayer = MapApi.CreateFeatureLayerInMemeory("點圖層", "點圖層", LocateHelper.GeoCoordinateSystem, esriGeometryType.esriGeometryPoint, null);
IFeature feature = featurelayer.FeatureClass.CreateFeature();
feature.Shape = startPoint;
feature.Store();
feature = featurelayer.FeatureClass.CreateFeature();
feature.Shape = endPoint;
feature.Store();

③    求解（這裏建議 try catch 一下）

int rowsIn = 0, rowsLocated = 0;
IFeatureCursor featureCursor = featurelayer.FeatureClass.Search(null, true);
classLoader.Load((ICursor)featureCursor, null, ref rowsIn, ref rowsLocated);
((INAContextEdit)m_NAContext).ContextChanged();

IGPMessages gpMessages = new GPMessagesClass();
m_NAContext.Solver.Solve(m_NAContext, gpMessages, null); //求解

好了，進行到這裏的時候就能看到導航效果了。附圖一張

遇到的問題：由於不存在 Network Analyst 許可，操作失敗。

參考官方例子 ClosestFacilitySolver 重新授權即可

參考資料：

http://resources.arcgis.com/zh-cn/help/main/10.1/index.html#//00470000005w000000

http://download.csdn.net/download/PMC_520/766131

http://blog.csdn.net/chanyinhelv/article/details/15498845