Go to menu:
Find -> Find in Files... (windows: ctrl+shift+f)
Switch on reg_ex button (windows: alt+r)
Find:

^.*\S+.*$

Where:

c:\your_folder\,*.php,*.js,*.inc,*.html,*.htm,*.scss, -*/folder_to_exclude/*, -*.min.js

Then click on the find button
Be careful to not click on Replace!!!
On the bottom line of your search result you'll find something like:
21342 matches in 124 files
This is you line count.