了解HTML5数据属性

Question

I am fairly new to javascript/jQuery, however I am making all efforts to understand what I am doing. I was inspired by diesel's site . On this site , data attributes are used for the text blocks on the home page. data-color . I want to achieve this function on my site . Being able to change the color of each block per entry, as the user scrolls down the page, it triggers differently.

I have come on here for help as I haven't seen any tutorial in relation to the functionality I am trying to achieve. Does anyone know how this can be done? I believe this would be helpful for those that want to execute the same or a similar functionality.

getColorMod: function(color, val) {
    var hexToRgb = function(hex) {
        var result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex);
        return result ? [parseInt(result[1], 16), parseInt(result[2], 16), parseInt(result[3], 16)] : false;
    }
    var array = hexToRgb(color),
    r = parseFloat(array[0] + val),
    g = parseFloat(array[1] + val),
    b = parseFloat(array[2] + val),
    rgb = array ? {
        r: r >= 250 ? 200 : r,
        g: g >= 250 ? 200 : g,
         b: b >= 250 ? 200 : b
    } : false;

    return 'rgb(' + rgb.r + ', ' + rgb.g + ', ' + rgb.b + ')';
},

Answer 1

The HTML5 data attribute is there simply for the purpose of storing additional information within html elements. I've used it when printing various sets of data programmatic-ly to include information like user account numbers. bits of data that you may want to access with javascript or jquery

You can see a great documentation/tutorial here on the HTML5 data attribute by webtutsplus

The data-attribute is interesting because you can define one as anything you like:

     data-[NAME]="[VALUE]"
     data-color="blue"
     data-price="$19.96"

The more recent versions of jQuery also have a built in easy to use function to deal specifically with getting and setting HTML5 data-attributes - documentation here

Imagine some hypothetical html:

     <span id="fluxCapacitor" data-gigawats="1.21"></span>

Calling the .data handler on our flux capacitor jquery element would return "1.21"

     $('#fluxCapacitor').data('gigawats'); // "1.21"

And you could use two parameter functionality for setting your flux capacitor to over 9000 gigawats.

     $('#fluxCapacitor').data('gigawats', "over 9000");

Resulting in:

     <span id="fluxCapacitor" data-gigawats="over 9000"></span>

---

edit: adjusted my power levels for historical accuracy.

Answer 2

<div class="bg">
    <div style="transition: background 500ms ease; -webkit-transition: background 500ms ease; background-color: rgb(25, 30, 36);"></div>
</div>

using library of your choice

This seems to be the way Diesel is performing the color transitions.

var $bodyBg = $('<div />'),
$bg = $('<div />').addClass('bg').append($bodyBg),
$arrow = $('<span />').addClass('arrow');

this.$navs.append($bg).append($arrow);

this.$navs
.on('hide', function() {
    // hide navigation bar
    $(this).addClass('hide');
})
.on('show', function() {
    // show navigation bar
    $(this).removeClass('hide');
})
.on('changeColor', $.proxy(function(e, color) {

    var $elm = $(e.currentTarget),
        $bg = $elm.find('.bg div');

    if (Modernizr.csstransforms && Modernizr.csstransitions) {
        // css3 transition
        $bg.css({
            transition: 'background 500ms ease',
            backgroundColor: this.getColorMod(color, 12)
        });
    } else {
        // no css3 transition support
        $bg.css({
            backgroundColor: this.getColorMod(color, 12)
        });
    }

}, this))
.trigger('hide')
.appendTo(this.$el);