ArcGIS AddIN开发:如何调用ArcMap中的选择工作空间的窗体

public static IWorkspaceName BrowseWorkspace(int hwnd,out IWorkspace ws)
{
IGxObjectFilterCollection ipFilters = new GxDialogClass();
//IGxObjectFilter ipFilter1 = new GxFilterFeatureDatasetsClass();  //要素数据集 ,导出时,IFeatureClassConverter对象无法写入Dataset中,此处隐藏掉
//ipFilters.AddFilter(ipFilter1,false);
IGxObjectFilter ifilt2 = new GxFilterWorkspacesClass();  //数据库工作空间,此类比较含糊,不知道具体指啥
ipFilters.AddFilter(ifilt2,false);
IGxObjectFilter ipFilter3 = new GxFilterFileFolderClass();  //文件工作空间
ipFilters.AddFilter(ipFilter3,false);

IGxDialog pGDialog = (IGxDialog)ipFilters;
pGDialog.RememberLocation = true;
pGDialog.Title = "请选择工作空间";
pGDialog.AllowMultiSelect = false;

IEnumGxObject pResultEnum = null;
//IWorkspace ws = null;
ws = null;
IWorkspaceName wsn = null;
if (pGDialog.DoModalOpen(hwnd, out pResultEnum) && pResultEnum != null)
{
IGxObject gxObj = pResultEnum.Next();
if (gxObj is IGxDatabase)
{
IGxDatabase gxDB = gxObj as IGxDatabase;
if (gxDB != null)
{
ws = gxDB.Workspace;
wsn = gxDB.WorkspaceName;
}
}
else if (gxObj is IGxFolder)
{
//Todo: figure out how to decide which workspace to get for
// a particular folder (shapefile, raster etc.)
//IEnumName enumName = ((IGxFolder)gxObj).FileSystemWorkspaceNames;

// for now just assume we want a shapefile ...
IWorkspaceFactory wsf = new ESRI.ArcGIS.DataSourcesFile.ShapefileWorkspaceFactoryClass();
ws = wsf.OpenFromFile(((IGxFile)gxObj).Path, hwnd);
IDataset pOutDataset = ws as IDataset;
wsn = pOutDataset.FullName as IWorkspaceName;
}
else if (gxObj is IGxDataset)
{
//如果是数据集工作空间
IGxDataset gxDs = gxObj as IGxDataset;
if (gxDs != null)
{
ws = gxDs.Dataset.Workspace;
wsn = gxDs.DatasetName.WorkspaceName;
}

}
Marshal.FinalReleaseComObject(pResultEnum);
}

pGDialog.InternalCatalog.Close();
Marshal.FinalReleaseComObject(pGDialog);

return wsn;
}