Create Next Previous Javascript Bookmarklet for Slideshow Tutorial Ebook sites

Recently I was browsing http://talks.php.net. There were bunch of slideshows about php. I work on PHP most times. So It was good for me.
The problem arise when I saw some slide shows didn’t rendered correctly in html. so there was no next, previous button. I had to change the urls to navigate next, previous pages.
Most urls were in the format http://domain.com/path/slideshow/1, where 1 is the page number. Changing it to 2 led me to the 2nd page of the sildeshow.
I wanted it to make automated. Via javascript obviously ( being a big fan of JS).

So I made two Javascript bookmarklet button. So when you click the Next button, it will go to next page. And same for Prev button.
Following are the buttons. All you have to do is just drag those button to your Browsers Bookmark bar. Thats it!

Next Page

Prev Page

Note: Not all the urls will work. See below to get more idea.

  1. http://domain.com/path/slideshow/1 Will work
  2. http://domain.com/path/slideshow/1.html Will not work
  3. http://domain.com/path/slideshow/1.php. Will not work
  4. http://domain.com/path/slideshow-1. Will work
  5. http://domain.com/path/slide-2/show Will not work
  6. http://domain.com/path/slide-2/show.php Will not work
  7. http://domain.com/path/slide-2 Will not work
  8. http://domain.com/path/slideshow#1 Will work ! !

Sometimes those buttons discussed above may not work, eg, Manual, ebook etc sites. In that case use the following two buttons.
These are quite handy if you are browsing a site where next page cannot be guessed from url.

Next URL

Prev URL

Here is the code

Next Button:

var e=document.getElementsByTagName("link");
var g="getAttribute";
var l=window.location.href;
for(i=0;i<e.length;i++){
    r=e[i][g]("rel").toLowerCase();
    h=e[i][g]("href");
    if(r=="next"){
    l=h;
    break;
    }
}

Previous Button:

var e=document.getElementsByTagName("link");
var g="getAttribute";
var l=window.location.href;
for(i=0;i<e.length;i++){
    r=e[i][g]("rel").toLowerCase();
    h=e[i][g]("href");
    if(r=="prev"){
    l=h;
    break;
    }
}