copy custom object properties to multiple objects

Question

blender 2.9 I have a custom object properties that need to be copied to ~1000 objects. I have done some research and using the script editor I am able to assign IDs to all of the objects and get a list of the properties I need to assign, however, I am a novice to python and I am stuck there.

Of course if there is an better way (addon?) to copy custom properties to multiple objects

Any help would be appreciated

Here is the script I used to assign the ids:

import bpy

objs = bpy.context.view_layer.objects.selected

numb = 1000

for obj in objs:
    obj["ID"] = str(numb)
    numb = numb + 1
    
for obj in bpy.context.view_layer.objects.selected:
    obj.select_set(state = True)

These are the custom properties I need to add:

Shake_Influence - 5.0
Shake_locX - 1.0
Shake_locY - 1.0
Shake_locZ - 1.0
Shake_rotX - 1.0
Shake_rotY - 1.0
Shake_rotz - 1.0

Answer 1

If not defined via UI.

The answer from https://blender.stackexchange.com/a/24004/123064 used in other answer will work for properties defined by the UI, or with the "_RNA_UI" key set. It is used for adding extra details to the property like min, max description, etc

It will not pick up on properties defined using

ob["foo"] = 3

Using ob.items() gives us a list of key, value pairs. The key being the name of the prop.

Test script,

import bpy

context = bpy.context
    
ob = context.object
# all props with name starting with "Shake_" on context ob
props = [(k, v) for k, v in ob.items() if k.startswith("Shake_")]

# all selected apart from ob
obs = context.selected_objects # selected
# obs = context.scene.objects[:] # all in scene
# obs = context.collection.objects[:] # all in context collection...
if ob in obs:
    obs.remove(ob)
# set from key value pairs
for o in obs:
    for k, v in props:
        o[k] = v
    

Related.

How to edit a custom property in a python script?

How can I save a dict in a scene propertyGroup?

how to change the value of various custom properties at the same time?

Get all custom properties of an object

When should custom-properties be used instead of 'bpy.props'?

Update a custom data field created with an addon

Answer 2

There is already a solution to copy custom-properties to and fro objects?

https://blender.stackexchange.com/a/24004/123064

import bpy

ob_sel = bpy.context.selected_editable_objects
ob_act = bpy.context.object

try:
    props = ob_act["_RNA_UI"]
except KeyError:
    pass
else:
    for ob in ob_sel:
        if ob == ob_act:
            continue
        for p in props.keys():
            print(p, ob_act[p])
            ob[p] = ob_act[p]

Note: I am not sure if you are trying to create custom-properties additionally from a script or just trying to transfer them.