I don't think you'll be able to do this. The PDF needs to be loaded into a reader, usually Adobe reader. Then the user needs to print from the reader's browser plugin. I don't think you can interact with the reader from client-side code. And the need to make this work with multiple documents complicates the matter. You could potentially use a PDF stitcher to stitch together all the PDFs the user selects into a single document, but this doesn't solve the printing problem.