How to pass parameter dynamically to JQuery click event from HTML elements?

Question

First of all, I have to mention that I am a newbie in the JavaScript and JQuery world. I am not sure if I put down an appropriate title for my question but I'll try my best to explain my problem.

Scenario: I have a list of items whose names are being displayed. When one of the items is being clicked, a popup should show up and display the description of the item. The description is retrieved from the server via an AJAX call upon the click. The AJAX call requires the unique id of the item (in the database) to be provided. Here comes my problem which has two parts:

1. I don't know how and where to include the item id in the HTML. Note that the list only displays item name not id.
2. Assume 1) is resolved, how can I pass the id of the item that's being clicked to the AJAX call.

This is the HTML of the list of items. As you can see, it illustrates part 1) of my problem (ie. don't know how to include the ids in the HTML).

<ul>
    <li class="item">Item1</li> <!-- this item has id=1 in the database -->
    <li class="item">Item2</li> <!-- this item has id=2 in the database -->
    <li class="item">Item3</li> <!-- this item has id=3 in the database -->
</ul>

Below is the JQuery click event handler that sends the AJAX call (ie. getJSON) to the server. Note that the part 2) of the problem is illustrated by the line var item_id = ??. Note that popup is a self-defined javascript.

    <script type="text/javascript" charset="utf-8">
        $(document).ready(function() {
            $(".item").click(function() {
                var item_id = ??
                var data = {"item_id":item_id};
                $.getJSON("/item/json", data, function(data) {
                    var name = data[0]["fields"]["name"]
                    var description = data[0]["fields"]["description"]
                    popup.call(this, name, description);
                });
            });
        });
    </script>

Additional Info: For the server side I use Django 1.3, and JQuery 1.5.2 for the client side. I hope I have made my question clear and I appreciate any help from you experts. Thanks.

Here is an example that is similar to what I am looking for.
http://esdi.excelsystems.com/iseries400apps/exmain.pgm?wsname=DIALOG.pgm&wsnumb=214&wsprogtype=P

Answer 1

http://www.w3schools.com/tags/tag_li.asp

The < li > tag supports the following standard attributes: id Specifies a unique id for an element

In this case use:

<ul>
    <li class="item" id="item_1">Item1</li> <!-- this item has id=1 in the database -->
    <li class="item" id="item_2">Item2</li> <!-- this item has id=2 in the database -->
    <li class="item" id="item_3">Item3</li> <!-- this item has id=3 in the database -->
</ul>

And

<script type="text/javascript" charset="utf-8">
    $(document).ready(function() {
        $(".item").click(function() {
            var item_id = $(this).attr('id').replace('item_','');
            var data = {"item_id":item_id};
            $.getJSON("/item/json", data, function(data) {
                var name = data[0]["fields"]["name"]
                var description = data[0]["fields"]["description"]
                popup.call(this, name, description);
            });
        });
    });
</script>

Answer 2

Javascript (and jQuery in particular) are used for client-side scripting. As such, you will need to supply the data within the HTML document. You can use jQuery' Metadata plug-in to supply the item ID:

<li class="item" data="{ItemID: 'Your_Item_ID'}">Item1</li>

and retrieve it via:

var item_id_structure = $(this).metadata().ItemID;