Dealing with Group Layers in scripts

Question

Hello,

I'm working on ArcGIS 9.3.1 and I run a python script which basically does a "select by location" query to several SDE layers which appear on the ArcMAP TOC (using a polygon shapefile the user points to) and copies the selected features to a new shapefile.

THE PROBLEM IS that some layers are within a group layer, and then the script gives a error stating :

<class 'arcgisscripting.ExecuteError'>: Failed to execute. Parameters are not valid.
ERROR 000840: The value is not a Feature Layer.
Failed to execute (SelectLayerByLocation)

now I understand that group layer is not a feature Layer and that SelectLayerByLocation only accepts feature Layers, that's where my question fits in:

Question: How can I reach a feature layer inside a Group layer using python code? or better yet, how can I tell what kind of layer I'm dealing with (Feature\group layer) using python code(describe method doesn't work on group)?

Thanks in Advance.

yonatanrubinstein · Answer

Hi, Dale - Thanks a million for trying to help me out.

I'm using a script tool - I run my script through ArcToolbox and a tool I built, so I guess your answer doesn't answer to my problem - but thanks, you've given me a idea to check maybe there is a tool background property that changing it will help me (i doubt it, but it's worth checking).

I'll return to say if this step will help in anyway but thanks in advance.

DaleHoneycutt · Answer

Are you running the script as a stand-alone script or as a script tool?  In order to use layers, you need a script tool that's running 'inside' arcmap.  See An overview of creating script tools for an explanation of script tools vs. stand-alone scripts.

Other than the above, I don't know why it's not working.

yonatanrubinstein · Answer

Sorry: use a forward slash instead of a backward slash, as in "Infrastructure/Streets"

Thanks, but unfortunately, this doesn't work either - the same error message as above is given by the system.