I have the need to modify (remove), select list items that are stored in the tblContentProperty/tblWorkContentProperty tables given certain criteria are met. Trying not to do this directly via SQL. Is there a way to access these select list items for a particular form if I supply the ID of the parent container of the form or the ID of the element itself? I know I can use ISelectionFactory to build a form element (select list), but can I also use it to retrieve? I'm using a scheduled job to do this work. And would modifying the entries with the select list items affect the drop down lists the way I think they should?
As I understand here you are modifying the select items of a Forms element? The element is a content so you can use CMS api to get it out then modify its propertis as you need then call save method. It is for safer than using the SQL directly.
I am not sure I understand exactly what end result you are trying to accomplish.
You want a dropdown inside a form, but not always show the same items inside that dropdown list? What are the dependencies?
If you think a drop-down list is the best suited element, and you want to control the items from code rather than adding them manually, I think creating a data feed is the way to go.
Simply create the datafeed as described here: https://world.episerver.com/blogs/hieu-nguyen-trung/dates/2017/2/create-data-feeds-for-episerver-forms/ and select that data feed from your drop-down list form element.