How to get element data within click function?

Question

Is there a tidier/easier way of getting the checkbox element's 'catNum' value when in its click() function?

function createCategoriesList() {

var catNames = new Array("First cat", "Second cat", "Third cat");
var catImageURLs = new Array("First.png", "Second.png", "Third.png");

jQuery('<ul/>', {
    id: 'map-cats'
}).appendTo('#map-controls');

for(var i = 0; i < catNames.length; i++ ) {

    var listItem = jQuery('<li/>').appendTo('#map-cats');

    jQuery('<img/>', {
        src: catImageURLs[i],
        alt: ''

    }).appendTo(listItem);

    var checkbox = jQuery('<input/>', {
        type: 'checkbox',
        checked: 'checked',
        id: 'cat_' + i,
        name: 'cat_' + i

    }).appendTo(listItem);
    checkbox.data("catNum", i);

    checkbox.click(function() {
        //alert("The cat num selected is: " + this.data("catNum")); //throws exception
        alert("The cat num selected is: " + jQuery('#' + this.id).data('catNum')); //works but there must be a better way??
    });

    jQuery('<label/>', {
        htmlFor: catImageURLs[i],
        text: catNames[i],
        for: 'cat_' + i

    }).appendTo(listItem);
}

}

Answer 1

checkbox.click(function() {
    alert("The cat num selected is: " + jQuery(this).data('catNum'));
});