ArcObjects - enumerating feature classes and datasets within a geodatabase

Question

I'm trying to enumerate the contents (feature classes and feature datasets, not interested in tables, etc) of a file geodatabase using vba/arcobjects.

I have the file GDB set as an IGxDatabase object, but can't find a way of getting further in. I've had a look at the geodatabase object model and tried using IFeatureClass and IFeatureDataset but neither seem to return useful results.

Thanks in advance for any assistance

Answer 1

It is much faster to enumerate the names contained in a geodatabase instead of the things that the names can open. The tricky part is looping through names in a featuredataset. While IFeatureWorkspace.Open can be used to open a featureclass without first opening the featuredataset that contains it, getting at featureclassnames within a featuredataset requires opening the featuredataset.

If you know for sure you'll need to open each featureclass, then I suppose it wouldn't hurt to use IWorkspace.Datasets, IEnumDataset, and IDataset instead of IWorkspaceDatasetNames, IEnumDatasetname and IDatasetname.

Option Explicit
Sub TestGetContents()
    Dim pGxApp As IGxApplication
    Set pGxApp = Application
    If Not TypeOf pGxApp.SelectedObject Is IGxDatabase Then
        Debug.Print "select a geodb first"
        Exit Sub
    End If
    Dim c As Collection
    Set c = GetContents(pGxApp.SelectedObject)
    Dim l As Long
    For l = 1 To c.Count
        Dim pName As IName
        Set pName = c.Item(l)
        If TypeOf pName Is IFeatureClassName Then
            Dim pFC As IFeatureClass
            Set pFC = pName.Open
            Debug.Print pFC.AliasName, pFC.FeatureCount(Nothing)
        ElseIf TypeOf pName Is IFeatureDatasetName Then
            Dim pDSName As IDatasetName
            Set pDSName = pName
            Debug.Print pDSName.name, "(featuredataset)"
        End If
    Next l
End Sub

Function GetContents(pGxDB As IGxDatabase) As Collection Dim c As New Collection Dim pEnumDSName As IEnumDatasetName Set pEnumDSName = pGxDB.Workspace.DatasetNames(esriDTAny) Dim pDSName As IDatasetName Set pDSName = pEnumDSName.Next Do Until pDSName Is Nothing If TypeOf pDSName Is IFeatureClassName Then c.Add pDSName ElseIf TypeOf pDSName Is IFeatureDatasetName Then c.Add pDSName AddSubNames pDSName, c End If Set pDSName = pEnumDSName.Next Loop Set GetContents = c End Function

Sub AddSubNames(pDSName1 As IDatasetName, c As Collection) Dim pEnumDSName As IEnumDatasetName Set pEnumDSName = pDSName1.SubsetNames pEnumDSName.Reset Dim pDSName2 As IDatasetName Set pDSName2 = pEnumDSName.Next Do Until pDSName2 Is Nothing If TypeOf pDSName2 Is IFeatureClassName Then c.Add pDSName2 End If Set pDSName2 = pEnumDSName.Next Loop End Sub