Solved
Get content from PDF
Do we have any extension or tools which have a method for get PDF file's content like LoadTxt service from FileRepository?
Here is one extension that uses pdf.js
\Tomcat 8.5\webapps\Thingworx\Common\extensions\ptc-thingview-extension\ui\thingview\js\ptc\thingview
contains pdf.js javascript extension.
https://github.com/mozilla/pdf.js/
Here is samples
https://mozilla.github.io/pdf.js/examples/index.html#interactive-examples
Searching thru Tomcat 8.5\webapps\Thingworx\Runtime\js\CombinedExtension...js
As noted in this community link https://community.ptc.com/t5/ThingWorx-Developers/Is-there-a-document-preview-widget-in-Thingworx/m-p/535582#M26123
you can also use WebFrame for displaying pdf