topic Re: arcpy.mapping.ListLayers in Python Questions

arcpy.mapping.ListLayers

MarkCollins1 — Thu, 01 Dec 2011 19:49:16 GMT

Hey all,

I have 20 features classes, each with multiple fields, but ALL containing a field titled "AFE_Number." I need to create a script to loop through a list of All feature classes and select any/all with the "AFE_Number" field containing a specific #. I am able to generate a list of the necessary features, but am unable to selectbyattribute for more than one at a time. Any suggestions? Thanks a bunch

Re: arcpy.mapping.ListLayers

JeffBarrette — Sat, 11 Dec 2021 18:29:03 GMT

SelectByAttribute works on only one FC at a time. Can't you simply build a list of FCs and loop through them.

lyrs = [lyr1, lyr2, lyr3, etc]
query = ' "AFE_Number' = SomeValue '
for lyr in lyrs:
  arcpy.SelectLayerByAttribute_management(lyr, "NEW_SELECTION", query)

Jeff

Re: arcpy.mapping.ListLayers

MarkCollins1 — Fri, 02 Dec 2011 15:42:20 GMT

I believe you are right about creating a list of fc's [a,b,c,...] and looping. Seems to be my only option. I appreciate your input. Im still new to the Python game and needed some advice. Thanks

Re: arcpy.mapping.ListLayers

MarkCollins1 — Fri, 02 Dec 2011 16:48:39 GMT

Is there a way to populate a list file via an arcpy.GetParameterAsText() ? Set a list [] variable equal to the value/s of a GetParametAsText. Seems like you could add the script in ArcMap and set the parameters as a multivalue and select all feature classes, then loop through them. Any ideas if something like this could work?

Re: arcpy.mapping.ListLayers

ChrisFox3 — Sat, 11 Dec 2021 18:29:06 GMT

Try this:

param1 = arcpy.getParameterAsText(0)
lyrList = param1.split(';')

The multivalue paramater will return you the values seperated by semi-colon if you use the split method on a string it will return you a list of items delimited by the character you pass into the method.