GeoDatabase

先看一下GeoDatabase核心结构模型图：

1 工作空间工厂WorkspaceFactory对象

WorkspaceFactory是GeoDatabase的入口，是一个抽象类，拥有很多子类，例如SdeWorkspaceFactory, AccessWorkspaceFactory, ShapfileWorkspaceFactory CadWorkspaceFactory等

IWorkspaceFactory接口定义了所有工作空间对象的一般属性和方法

   public IWorkspaceName Create (string parentDirectory,string Name,IPropertySet ConnectionProperties,int hWnd);用于产生一个新的工作空间名称对象，前两个参数是数据库的路径和名称，第三个参数是一个属性集（properset）对象。

   public IWorkspace Open ( IPropertySet ConnectionProperties,int hWnd);打开一个已经存在的工作空间像SDE数据库等；

public IWorkspace OpenFromFile (string fileName,int hWnd);打开一个文件类型的数据

2 工作空间WorkSpace对象

Workspace在逻辑上是一个包含空间数据集和非空间数据集的数据容器，数据包括要素类、栅格数据集、表等对象

Workspace对象主要的一些接口：

1 IWorkspace接口：定义了一个工作空间最普通的属性和方法。

2 IFeatureWorkspace接口

这个接口主要用于管理要素的数据集，如表（Table）、对象类（ObjectClass）、要素类（FeatureClass）、要素数据集（FeatureDataset）和关系类（RelationshipClass）等。

主要的成员：

   public IFeatureClass OpenFeatureClass ( string Name) 打开一个已经存在的要素类，无论这个要素类是在工作空间还是在一个要素数据集中

    public IFeatureDataset OpenFeatureDataset (string Name);打开一个已经存在的要素数据集

    public ITable OpenTable (string Name);打开一个已经存在的表；

3 RasterWorkspace对象

主要实现了IRasterWorkspace接口

    public IRasterDataset OpenRasterDataset ( string Name);

4 属性集Propertyset对象

Propertyset对象是一个专门用于设置属性的对象，它是一种name-value对应的集合，类似于Hash表。属性名必须是字符串，属性值可以是字符串、数值或日期也可以是一个对象

  public void SetProperty (string Name, object Value);

5 DataSet数据集对象

Dataset对象可分为两大类：Table和GeoDataset，GeoDataset是一个抽象类，代表了拥有空间属性的数据集，包括FeatureDataset、要素类FeatureClass、TIN和栅格数据集RasterDataset。

6 FeatureDataset对象

实现的主要接口

1 IFeatureDataset接口

public IEnumDataset Subsets {get;}：Datasets contained within this dataset.

2 IFeatureClassContainer接口

用于管理要素数据集里面的要素类，该接口的ClassByName和Class（index）等属性可以用来获取数据集中的特定的要素类（这里很奇怪在帮助文档中只有属性没有方法但点进去却是一个方法Ok你大概不理解我说的）

public IFeatureClass get_Class (int ClassIndex);

public IFeatureClass get_ClassByID (int ID);

public IFeatureClass get_ClassByName (string Name);

例子

1 加载Shapefiles文件

OpenFileDialog dlg=new OpenFileDialog();
dlg.Title="打开shapefile文件";
dlg.Filter="(*.shp)|*.shp";
dlg.ShowDialog();
string filename=dlg.FileName;
int index=filename.LastIndexOf(@"\");
string path=filename.Substring(0,index);
string name=filename.Substring(index+1);
IWorkspaceFactory pWsFactory = new ShapefileWorkspaceFactoryClass();
IFeatureWorkspace  pWorkSpace = pWsFactory.OpenFromFile(path, 0) as IFeatureWorkspace;
IFeatureClass pFeatureClass = pWorkSpace.OpenFeatureClass(name);
IFeatureLayer pFeatureLayer = new FeatureLayerClass();
pFeatureLayer.Name = pFeatureClass.AliasName;
pFeatureLayer.FeatureClass = pFeatureClass;
axMapControl1.Map.AddLayer(pFeatureLayer);
axMapControl1.ActiveView.PartialRefresh(esriViewDrawPhase.esriViewGraphics, null, null);

2.加载栅格数据

OpenFileDialog dlg = new OpenFileDialog();
dlg.Title = "打开Raster文件";
dlg.Filter = " Layer File(*.lyr)|*.jpg;*.bmp;*.tiff ";
dlg.ShowDialog();
string filename = dlg.FileName;
int index = filename.LastIndexOf(@"\");
string path = filename.Substring(0, index);
string name = filename.Substring(index + 1);
IWorkspaceFactory pWsFactory =new RasterWorkspaceFactoryClass();
IRasterWorkspace pRasterWorkspace = pWsFactory.OpenFromFile(path, 0) as IRasterWorkspace;
IRasterDataset pRasterDataset = pRasterWorkspace.OpenRasterDataset(name);
IRasterLayer pRasterLayer = new RasterLayerClass();
pRasterLayer.CreateFromDataset(pRasterDataset);
axMapControl1.Map.AddLayer(pRasterLayer);
axMapControl1.ActiveView.PartialRefresh(esriViewDrawPhase.esriViewGraphics, null, null);

3 加载CAD数据

OpenFileDialog dlg = new OpenFileDialog();
dlg.Title = "打开CAD文件";
dlg.Filter = " CAD(*.dwg)|*.dwg|All Files(*.*)|*.* ";
dlg.ShowDialog();
string filename = dlg.FileName;
int index = filename.LastIndexOf(@"\");
string path = filename.Substring(0, index);
string name = filename.Substring(index + 1);
IWorkspaceFactory pWsFactory = new CadWorkspaceFactoryClass();
IFeatureWorkspace pFeatureWorkspace = pWsFactory.OpenFromFile(path, 0) as IFeatureWorkspace;
IFeatureDataset pFeatureDataset = pFeatureWorkspace.OpenFeatureDataset(name);
IFeatureClassContainer pFCContainer = pFeatureDataset as IFeatureClassContainer;
for (int i = 0; i < pFCContainer.ClassCount; i++)
{
    IFeatureClass pFeatureClass = pFCContainer.get_Class(i);
    if (pFeatureClass.FeatureType == esriFeatureType.esriFTCoverageAnnotation)
    {
        IFeatureLayer pFeatureLayer = new CadAnnotationLayerClass();
    }
    else
    {
        IFeatureLayer pFeatureLayer = new FeatureLayerClass();
        pFeatureLayer.FeatureClass = pFeatureClass;
        pFeatureLayer.Name = pFeatureClass.AliasName;
        axMapControl1.Map.AddLayer(pFeatureLayer);
    }
    axMapControl1.ActiveView.PartialRefresh(esriViewDrawPhase.esriViewGraphics, null, null);

4 加载PersonGeodatabase数据

OpenFileDialog dlg = new OpenFileDialog();
dlg.Title = "打开Geodatabase文件";
dlg.Filter = " Personal Geodatabase(*.mdb)|*.mdb|All Files(*.*)|*.* ";
dlg.ShowDialog();
string path = dlg.FileName;
           
IWorkspaceFactory pAccessWorkspaceFactory;
IFeatureWorkspace pFeatureWorkspace;
IFeatureLayer pFeatureLayer;
IFeatureDataset pFeatureDataset;
pAccessWorkspaceFactory = new AccessWorkspaceFactoryClass();
          
IWorkspace pWorkspace = pAccessWorkspaceFactory.OpenFromFile(path, 0);
IEnumDataset pEnumDataset = pWorkspace.get_Datasets(ESRI.ArcGIS.Geodatabase.esriDatasetType.esriDTAny);
pEnumDataset.Reset();
IDataset pDataset = pEnumDataset.Next();
           
if (pDataset is IFeatureDataset)
{
    pFeatureWorkspace = (IFeatureWorkspace)pAccessWorkspaceFactory.OpenFromFile(path, 0);
    pFeatureDataset = pFeatureWorkspace.OpenFeatureDataset(pDataset.Name);
    IEnumDataset pEnumDataset1 = pFeatureDataset.Subsets;
    pEnumDataset1.Reset();
    IDataset pDataset1 = pEnumDataset1.Next();
   
    if (pDataset1 is IFeatureClass)
    {
        pFeatureLayer = new FeatureLayerClass();
        pFeatureLayer.FeatureClass = pFeatureWorkspace.OpenFeatureClass(pDataset1.Name);
        pFeatureLayer.Name = pFeatureLayer.FeatureClass.AliasName;
        axMapControl1.Map.AddLayer(pFeatureLayer);
        axMapControl1.ActiveView.Refresh();
    }
   
  
}
else
{
    pFeatureWorkspace = (IFeatureWorkspace)pWorkspace;
    pFeatureLayer = new FeatureLayerClass();
    pFeatureLayer.FeatureClass = pFeatureWorkspace.OpenFeatureClass(pDataset.Name);
    pFeatureLayer.Name = pFeatureLayer.FeatureClass.AliasName;
    axMapControl1.Map.AddLayer(pFeatureLayer);
    axMapControl1.ActiveView.Refresh();
}