SharePoint Custom file attachment control

Attach multiple files to SharePoint list item with custom upload control.
we can do the below features to your file upload control

1. Add Client Validation
2. Avoid duplicate file upload error
3. upload multiple attachments
4. include each document comments

Here we can use Custom Upload Control and OOB Attachments table.

HTML Code for Attachment Control:

Now we will include all feature step by Step

Step: 1
   
Client Validation for SharePoint file Upload Control

Step: 2
 Stop Showing duplicate file upload Error

Step: 3
 SharePoint add comments for each attached document