List all features classes in a particular dataset

MapWinGIS
1

I could successfully loop through all feature classes in ESRI-geodatabase features. But, some of these features resides inside dataset. How can I list all feature classes in one particular dataset.
Thanks

2

Hello @alrajhi20

I’m not sure I fully understand your question. It might help to provide a little sample code, showing how you are trying to read the Feature Classses and Datasets.

As you may know, MapWinGIS uses the GDAL library for all non-Shapefile datasources. So it might also help to review the GDAL documentation regarding the ESRI GDB Driver.

Regards,
Jerry.

3

Hi Mr. Jerry,
I have a esri-geodatabase that has multiple datasets. All other feature classes are classified inside these datasets. See picture:
ds
Now for example, I just want to list all feature class in AeronauticalInformation dataset only. I am not interested in other datasets.
Well, your statement: “As you may know, MapWinGIS uses the GDAL library for all non-Shapefile datasources” is very helpful, so I will look at GDAL library to find out how.
Thanks

4

Hi Mr. Jerry,
I really could not find a clean and understandable code of GDAL library for my problem.
Would you please guide me with code or with link.
Thanks in advance

5

Are you able/allowed to upload the AeronauticalInformation dataset? I don’t know what the GDB looks like through through the API, but I could have a look and try some things.

Regards,
Jerry.

6

I don’t know what do you mean with “upload the AeronauticalInformation dataset”. but I have this gdb in my C# winforms application.
I would appreciate it if you could have a look to my sample esri geodatabase attached. Try to for example to list feature classes in Metadata dataset.
sample.zip (2.1 MB)

Thanks in advance

7

Hello @alrajhi20

I don’t see a Metadata dataset. What I see are 5 layers, being
index_100k, index_50k, Road, BuildUpArea, and Enclosure.

And each of the layers have a number of Features, as displayed below (zoomed in to the significant area).

Here is the code I used:

Dim ds As New OgrDatasource()
Dim cs As String = "c:\temp\sample\data.gdb"
If ds.Open(cs) Then
    Dim layers As Integer = ds.LayerCount
    For i = layers - 1 To 0 Step -1
        Dim layerName As String = ds.GetLayerName(i)
        Debug.WriteLine(layerName)
        Dim ogr As OgrLayer = ds.GetLayer(i)
        AxMap1.AddLayer(ogr, True)
    Next
    AxMap1.ZoomToMaxVisibleExtents()
End If

Is this not what you expected?

image

Regards,
Jerry.

8

Hi Mr. Jerry,
Thanks for your reply.
I already could load these features in my map. My real problem is that for some reason I need to display only indexes index_100k and index_50k in my map. I somehow want to get the dataset name for each feature class in my OgrDatasource.
Thanks

9

Ok. Did you see in my sample code that you can get the name on each iteration, and then only load the ones you want. Something like:

Dim ds As New OgrDatasource()
Dim cs As String = "c:\temp\sample\data.gdb"
If ds.Open(cs) Then
    Dim layers As Integer = ds.LayerCount
    For i = layers - 1 To 0 Step -1
        Dim layerName As String = ds.GetLayerName(i)
        Debug.WriteLine(layerName)
        If layerName.Substring(0, 5) = "index" Then
            Dim ogr As OgrLayer = ds.GetLayer(i)
            AxMap1.AddLayer(ogr, True)
        End If
    Next
    AxMap1.ZoomToMaxVisibleExtents()
End If

I don’t know if you’re using VB or c#, but the syntax is similar.

Regards,
Jerry.

10

Well, this code will solve a particular case when feature class name starts with “index”, but code doesn’t yet solve the problem.
I am using C#

11

I’m sorry, but this is what I understood you to be saying was the problem. So I guess I don’t understand what you are asking.

12

Sorry, maybe the way I had written the question does not clearly say it.
To be more clear:
I want the application to enable user to select file geo-database. then application will list all datasets in selected geo-database. Then when user select a particular dataset from drop down list for example, application will list all feature classes within selected dataset.
This is main goal.