Setting selection method in ArcPy?

Question

I haven't found a way of setting the selection method (Create new, Add to current, Remove from current, Select from current selection) in arcpy. Is it possible to do this and - if yes - how?

I am switching between these methods regularly and having to press a modifier key is somewhat error-prone, so I'd like to create a python add-in toolbar that allows me to select the method directly.

Also, I want to select interactively because the features are more or less picked by gut feeling.

Answer 1

arcpy.SelectLayerByAttribute_management and arcpy.SelectLAyerByLocation management both have the optional parameter Selection Type. The value must be one of the following strings:

• "NEW_SELECTION"
• "ADD_TO_SELECTION"
• "REMOVE_FROM_SELECTION"
• "SUBSET_SELECTION"
• "SWITCH_SELECTION"
• "CLEAR_SELECTION"

Answer 2

While not answering the specific question, I try to aim at the functionality the OP is seeking. I often use these different selection methods myself, and for convenience I have added a dropdown list to my toolbar (and rearranged some of the other buttons):

If this is not enough for you, I'd suggest using the built-in system for creating keyboard shortcuts. You can access it from Customize --> Customize mode --> Keyboard... (This is also the place for adding and rearranging buttons.)

There you can create a custom shortcut for, virtually, any function or button in Arcmap.

Answer 3

Yo can do selection by both attribute using arcpy.SelectLayerByAttribute_management and location using arcpy.SelectLayerByLocation_management, but you cannot do selection directly from feature, you should create a temporary layer using arcpy.MakeFeatureLayer_management before doing a selection.

Here is snippet code from the above help:

# Import system modules
import arcpy

# Set the workspace
env.workspace = "c:/data/mexico.gdb"

# Make a layer from the feature class
arcpy.MakeFeatureLayer_management("cities", "lyr") 

# Select all cities which overlap the chihuahua polygon
arcpy.SelectLayerByLocation_management("lyr", "intersect", "chihuahua", 0, "new_selection")

# Within selected features, further select only those cities which have a population > 10,000   
arcpy.SelectLayerByAttribute_management("lyr", "SUBSET_SELECTION", ' "population" > 10000 ')

# Write the selected features to a new featureclass
arcpy.CopyFeatures_management("lyr", "chihuahua_10000plus")

Answer 4

Setting the selection method is an option on the Select Layer By Attributes tool.

However, I am not sure that a Python AddIn will offer the advantage you seek here.