When opening a Form (Disp, Edit), I'd like to determine the number of attachments listed in a List item along with the overall size, and created/modified dates of all attachments.
Hi Marc Bernard
We do not have specific functionality for attachment handling since attachments in SharePoint are very limited - there is no metadata on these files like created/modified neither versioning or other features you have available in document libraries.
We recommend to use document libraries as sublibraries of the main item where you added your attachments in the past. Just create a lookup column targetting the main list on your document library you want to store your related files.
Then click on "Insert Sublibrary" from the ribbon on your customized main list form.
For the determining number of documents we don't have a ready-to-use script. But you're may able to configure a validation on a field where you sum the number of related documents by a custom script that looks like this:
Retrieving data ...