How to send a parameter to the each function in Jquery

I'm trying to paginate an image gallery using jquery. The image directory I'm using contains about 600 images, named like th开发者_开发百科is: "photo1.jpg" ... "photo(n).jpg" ... "photo600.jpg".

Suppose I have a variable holding the page number var page and there are 40 images on each virtual page. I want to do something like:

for (var i = 0; i<40; i++){
      var imageNum = (((page*40)-40)+i+1);
      $("img")[i].attr("src","photo"+ imageNum + ".jpg"); // Doesn't work
   }
}

This is hackish but do you see what I am trying to do? The jquery API had some info on using each() to iterate through a jquery object but i couldn't figure out how to send the each function a parameter holding data about which page I am on, which I will need to determine the paths to the images. I'm going for something like:

$("img").each(function (i) {
        //code to update image paths based on page parameter
      });

I'm open to different approaches as well, I am a total noob and I feel like I might be going about this in the wrong way to begin with :S.

Edit Thanks to everyone for their answers.

If you are looking for a quick and simple answer that works using each(), check out Jeff B's answer.

I accepted patrick dw's answer because it goes into a bit more detail about a separate mistake I was making and covers another approach as well. Also, please see our comments on his response if you are like me and thought you needed to pass parameters to .each().

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This doesn't work because [i] gives you a native DOM element that is not wrapped in a jQuery object.

jQuery has the eq()^[docs] method to give you the element wrapped so you can call the attr()^[docs] method.

   // Do NOT run the selector inside the loop
var imgs = $("img");

for (var i = 0; i<40; i++){
      var imageNum = (((page*40)-40)+i+1);
      imgs.eq( i ).attr("src","photo"+ imageNum + ".jpg"); // Doesn't work
   }
}

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As an alternative, you can pass a function directly to the attr()^[docs] method that will loop over the elements for you.

$("img").attr( 'src', function(i) {
    return "photo" + (((page*40)-40)+i+1) + ".jpg";
});

The return value is the value that will be assigned to the attribute you're setting (which is src in this case).

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The .each() function passes an index, (and value if you desire) for you:

$("img").each( function(idx) {
    $(this).attr("src","photo"+ (((page*40)-40)+idx+1) + ".jpg");
});

Example: (similar, but modified to use placeholders)

http://jsfiddle.net/mEzR9/

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Second approach is more pretty of course but first one will also work.

You should use this: $($("img")[i]).attr(...)