使用HTML5技术开发的超酷颜色选择器.doc

六年老品牌 值得信赖！可能大家见过很多使用jquery/js开发的颜色选择器，今天这里我们将使用HTML5技术来自己实现一个更棒的颜色选择器。希望大家喜欢！HTML代码 R G B RGB HEX 代码很简单，包含了2个部分，一个点击元素，一个用来展示颜色选择器的元素。Javascript代码$(function() var bCanPreview = true; / can preview / create canvas and context objects var canvas = document.getElementById(picker); var ctx = canvas.getContext(2d); / drawing active image var image = new Image(); image.onload = function () ctx.drawImage(image, 0, 0, image.width, image.height); / draw the image on the canvas / select desired colorwheel var imagesrc=images/colorwheel1.png; switch ($(canvas).attr(var) case 2: imagesrc=images/colorwheel2.png; break; case 3: imagesrc=images/colorwheel3.png; break; case 4: imagesrc=images/colorwheel4.png; break; case 5: imagesrc=images/colorwheel5.png; break; image.src = imageSrc; $(#picker).mousemove(function(e) / mouse move handler if (bCanPreview) / get coordinates of current position var canvasOffset = $(canvas).offset(); var canvasX = Math.floor(e.pageX - canvasOffset.left); var canvasY = Math.floor(e.pageY - canvasOffset.top); / get current pixel var imageData = ctx.getImageData(canvasX, canvasY, 1, 1); var pixel = imageData.data; / update preview color var pixelColor = rgb(+pixel0+, +pixel1+, +pixel2+); $(.preview).css(backgroundColor, pixelColor); / update controls $(#rVal).val(pixel0); $(#gVal).val(pixel1); $(#bVal).val(pixel2); $(#rgbVal).val(pixel0+,+pixel1+,+pixel2); var dColor = pixel2 + 256 * pixel1 + 65536 * pixel0; $(#hexVal).val(# + (0000 + dColor.toString(16).substr(-6); ); $(#picker).click(function(e) / click event handler bCanPreview = !bCanPreview; ); $(.preview).click(function(e) / preview click $(.colorpicker).fadeToggle(slow, linear); bCanPreview = true; ););大家可以看到，这是一个非常短的js代码，用来创建新的画布和对象，然后我们画出一个圆形的颜色板。你可以选择不同颜色底板。 这里使用一个参数来设定不同的选择。如下：下面我们添加事件：mousemove，click事件。这里使用jQuery来实现选择器的展现和隐藏。$(.preview).click(function(e) / preview click $(.colorpicker).fadeToggle(slow, linear); bCanPreview = true; );当我们的鼠标移动到选择对象上，我们需要刷新信息，例如，目前颜色$(#picker).mousemove(function(e) / mouse move handler if (bCanPreview) / get coordinates of current position var canvasOffset = $(canvas).offset(); var canvasX = Math.floor(e.pageX - canvasOffset.left); var canvasY = Math.floor(e.pageY - canvasOffset.top); / get current pixel var imageData = ctx.getImageData(canvasX, canvasY, 1, 1); var pixel = imageData.data; / update preview color var pixelColor = rgb(+pixel0+, +pixel1+, +pixel2+); $(.preview).css(backgroundColor, pixelColor); / update controls $(#rVal).val(pixel0); $(#gVal).val(pixel1); $(#bVal).val(pixel2); $(#rgbVal).val(pixel0+,+pixel1+,+pixel2); var dColor = pixel2 + 256 * pixel1 + 65536 * pixel0; $(#hexVal).val(# + (0000 + dColor.toString(16).substr(-6); );$(#picker).click(function(e) / click event handler bCanPreview = !bCanPreview;);CSS代码不同颜色底板的CSS：/* colorpicker styles */.colorpicker background-color: #222222; border-radius: 5px 5px 5px 5px; box-shadow: 2px 2px 2px #444444; color: #FFFFFF; font-size: 12px; position: absolute; width: 460px;#picker cursor: crosshair; float: left; margin: 10px; border: 0;.controls float: right; margin: 10px;.controls div border: 1px solid #2F2F2F; margin-bottom: 5px; overflow: hidden; padding: 5px;.controls label float: left;.controls div input background-color: #121212; border: 1px solid #2F2F2F; color: #DDDDDD; float: right; font-size: 10px; height: 14px; margin-left: 6px; text-align: center; text-transform: uppercase; width: 75px;.preview background: url(./images/select.png) repeat scroll center