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Greasemonkey Hacks
book

Greasemonkey Hacks

by Mark Pilgrim
November 2005
Intermediate to advanced
496 pages
11h 9m
English
O'Reilly Media, Inc.
Content preview from Greasemonkey Hacks

Hack #17. Warn Before Opening PDF Links

Make your browser double-check that you really want to open that monstrous PDF.

How many times has this happened to you? You're searching for something, or just browsing, and click on a promising-looking link. Suddenly, your browser slows to a crawl, and you see the dreaded "Adobe Acrobat Reader" splash screen. Oh no, you've just opened a PDF link, and your browser is launching the helper application from hell.

This hack saves you the trouble, by popping up a dialog box when you click on a PDF file to ask you if you're sure you want to continue. If you cancel, you're left on the original page and can continue browsing in peace.

Tip

This hack is derived from a Firefox extension called TargetAlert, which offers more features and customization options. Download it at http://bolinfest.com/targetalert/.

The Code

This user script runs on all pages. It iterates through the document.links collection, looking for links pointing to URLs ending in .pdf. For each link, it attaches an onclick handler that calls the window.confirm function to ask you if you really want to open the PDF document.

Save the following user script as pdfwarn.user.js:

	// ==UserScript==
	// @name          PDF Warn
	// @namespace     http://www.sencer.de/
	// @description   Ask before opening PDF links
	// @include       *
	// ==/UserScript==

	// based on code by Sencer Yurdagül and Michael Bolin
	// and included here with their gracious permission
	// http://www.sencer.de/code/greasemonkey/pdfwarn.user.js for (var ...
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Publisher Resources

ISBN: 0596101651Errata Page