How to programmatically disable ECB menu item for a particular list item?

Question

I have a custom document library which is based on default document library. I'd like to disable Edit physical document for some of the documents depending on their property.

Answer 1

If you don't mind a client side solution then you can use either a single Content Editor Web Part to inject some JavaScript on a single page or execute the script on every page in the site collection using our free SharePoint Infuser.

Plenty of examples, although not your particular problem, can be found here.