打開cad文件的幾種方法

　　方法一、通過遍歷CAD數據集，依次加載中點線面注記等圖層，所加載的數據均為一個獨立的圖層。

　　IWorkspaceFactory pWorkspaceFactory;
　　IFeatureWorkspace pFeatureWorkspace;
　　IFeatureLayer pFeatureLayer;
　　IFeatureDataset pFeatureDataset;
　　//打開CAD數據集
　　pWorkspaceFactory = new CadWorkspaceFactoryClass();
　　pFeatureWorkspace = (IFeatureWorkspace)pWorkspaceFactory.OpenFromFile(directoryPath, 0);
　　//打開一個要素集
　　pFeatureDataset = pFeatureWorkspace.OpenFeatureDataset(fileName);
　　//IFeaturClassContainer可以管理IFeatureDataset中的每個要素類
　　IFeatureClassContainer pFeatureClassContainer = (IFeatureClassContainer)pFeatureDataset;
　　//對CAD文件中的要素進行遍歷處理
　　for (int i = 0; i < pFeatureClassContainer.ClassCount - 1; i++)
　　{
　　IFeatureClass pFeatureClass = pFeatureClassContainer.get_Class(i);
　　if (pFeatureClass.FeatureType == esriFeatureType.esriFTAnnotation)
　　{
　　//如果是注記，則添加注記層
　　pFeatureLayer = new CadAnnotationLayerClass();
　　}
　　else//如果是點、線、面，則添加要素層
　　{
　　pFeatureLayer = new FeatureLayerClass();
　　pFeatureLayer.Name = pFeatureClass.AliasName;
　　pFeatureLayer.FeatureClass = pFeatureClass;
　　this.axmc_Main.Map.AddLayer(pFeatureLayer);
　　this.axmc_Main.ActiveView.**();
　　}

　　}

　　方法二、直接打開CAD數據的點線面注記等要素類，所加載的數據均為一個獨立的圖層。

　具體代碼如下:

   CadWorkspaceFactoryClass fac=new CadWorkspaceFactoryClass ();
   String filePath="E:\cad";
   IFeatureWorkspace space=fac.OpenFromFile(filePath,0) as IFeatureWorkspace ;
   下面是打開FeatureClass的代碼：
   //線
   IFeatureClass polyline =space.OpenFeatureClass("NewCAD.dwg:Polyline");  
   IFeatureLayer layer=new CadFeatureLayerClass ();
   layer.FeatureClass =polyline;
   //點
   IFeatureClass point=space.OpenFeatureClass ("NewCAD.dwg:Point");
   layer=new CadFeatureLayerClass ();
   layer.FeatureClass =point;
   //面  
   IFeatureClass polygon=space.OpenFeatureClass ("NewCAD.dwg:Polygon");
   ayer=new CadFeatureLayerClass();
   layer.FeatureClass =polygon;
   //注記  
   IFeatureClass anno=space.OpenFeatureClass ("NewCAD.dwg:Annotation");
   layer=new CadAnnotationLayerClass();
   layer.FeatureClass =anno;
//其實在Coverage文件的開發方式與Autocad方法類似,可以參考.

　　方法三、利用繪圖空間直接加載CAD數據集，加載后各類型數據作為一個圖層顯示。

　　

　　IWorkspaceFactory pWorkspaceFactory = new CadWorkspaceFactoryClass();

　　IWorkspace pWorkspace = pWorkspaceFactory.OpenFromFile(directoryPath, 0);

　　//--定義一個CAD畫圖空間，并把上邊打開的工作空間賦給它

　　ICadDrawingWorkspace pCadDrawingWorkspace = pWorkspace as ICadDrawingWorkspace;#p#分頁標題#e#

　　//--定義一個CAD的畫圖數據集，并且打開上邊指定的工作空間中一幅CAD圖

　　//--然后賦值給CAD數據集

　　ICadDrawingDataset pCadDrawingDataset = pCadDrawingWorkspace.OpenCadDrawingDataset(fileName);

　　//--通過ICadLayer類，把上邊得到的CAD數據局賦值給ICadLayer類對象的

　　//--CadDrawingDataset屬性

　　ICadLayer pCadLayer = new CadLayerClass();

　　pCadLayer.CadDrawingDataset = pCadDrawingDataset;

　　//--利用MapControl加載CAD層

　　this.axmc_Main.Map.AddLayer(pCadLayer);
　　this.axmc_Main.ActiveView.**();

　　方法四、也是遍歷CAD點線面，但是不用檢查數據類型是否為注記。

　　IWorkspaceFactory pWorkspaceFactory = new CadWorkspaceFactoryClass();
　　IFeatureWorkspace pFeatureWorkspace = pWorkspaceFactory.OpenFromFile(directoryPath, 0) as IFeatureWorkspace;
　　IFeatureDataset pFeatureDataset = pFeatureWorkspace.OpenFeatureDataset(fileName);
　　IFeatureClassContainer pFeatureClassContainer = (IFeatureClassContainer)pFeatureDataset;
　　for (int i = 0; i < pFeatureClassContainer.ClassCount - 1; i++)
　　{
　　IFeatureClass pFeatureClass = pFeatureClassContainer.get_Class(i);
　　IFeatureLayer pFeatureLayer = new FeatureLayerClass();
　　pFeatureLayer.FeatureClass = pFeatureClass;
　　//ICadLayer pCadLayer = new CadLayerClass();
　　//pCadLayer = pFeatureLayer as ICadLayer;
　　this.axmc_Main.Map.AddLayer(pFeatureLayer);
　　this.axmc_Main.ActiveView.**();

　　}

　　方法五、類似與方法三。

　　//Add passed file to MapControl
　　ICadDrawingDataset pCadDrawingDataset = GetCadDrawingDataset(directoryPath, fileName);
　　if (pCadDrawingDataset == null) return;
　　ICadLayer pCadLayer = new CadLayerClass();
　　pCadLayer.CadDrawingDataset = pCadDrawingDataset;
　　pCadLayer.Name = fileName;
　　this.axmc_Main.AddLayer(pCadLayer, 0);

　　/// <summary>
　　/// 獲取記錄集
　　/// </summary>
　　/// <param name="directoryPath"></param>
　　/// <param name="fileName"></param>
　　/// <returns></returns>
　　private ICadDrawingDataset GetCadDrawingDataset(string directoryPath, string fileName)
　　{
　　//Create a WorkspaceName object
　　IWorkspaceName pWorkspaceName = new WorkspaceNameClass();
　　pWorkspaceName.WorkspaceFactoryProgID = "esriDataSourcesFile.CadWorkspaceFactory";
　　pWorkspaceName.PathName = directoryPath;
　　//Create a CadDrawingName object
　　IDatasetName pDatasetName = new CadDrawingNameClass();
　　pDatasetName.Name = fileName;
　　pDatasetName.WorkspaceName = pWorkspaceName;
　　//Open the CAD drawing
　　IName pName = (IName)pDatasetName;
　　return (ICadDrawingDataset)pName.Open();