How to programatically open a PDF with a User password

问题

This is related to my other question... hope this one has a solution.

The requirement is to display a password-protected PDF in the browser but to pass the User password programatically. I create a PDF using Jasper and set the user password as follows:
exporter.setParameter(JRPdfExporterParameter.USER_PASSWORD, userPassword);

As soon as the PDF is created, it has to be displayed in the screen. While displaying in the browser, the user should not be prompted to key in the password ans hence the password should be supplied by the application However, if the user downloads the PDF and then tries to open it, he should be prompted to enter the password.
[Edit]: I am looking for an approach that does NOT involve licensed tools

回答1:

I'm not sure whether something of this is possible. On the browser the pdf is opened by a Plugin - usually Adobe Reader plug-in. There are also other makes apart from Adobe Reader. Chrome has it own plugin.

On the browser when it detects any PDF file - the rendering plugin takes over - and this is browser specific. You hardly have any control.

Easy alternative is to show the same content in a web page - probably a modal window if the content is sensitive and give a link to download the password protected pdf file

my 2c

回答2:

You can open a password protected PDF using the PDF.JS library.

PDFJS.getDocument({ url: pdf_url, password: pdf_password }).then(function(pdf_doc) {
    // success
}).catch(function(error) {
    // incorrect password

    // error is an object having 3 properties : name, message & code
});

I've written a blog post on it, also containing a demo. This is the link : http://usefulangle.com/post/22/pdfjs-tutorial-2-viewing-a-password-protected-pdf

回答3:

You could checkout PDF.js, an open source client based PDF renderer that also has support for encrypted PDFs. http://mozilla.github.com/pdf.js/

This means you will have to put your password somewhere in the javascript though, so you will have to disguise it, but it should do the trick :)

来源：https://stackoverflow.com/questions/14602102/how-to-programatically-open-a-pdf-with-a-user-password