cropbox插件实现的头像裁剪效果
html代码
<!DOCTYPE html> <html> <head lang="en"> <meta charset="UTF-8"> <!--[if lt IE 9]> <script src="//cdnjs.cloudflare.com/ajax/libs/html5shiv/r29/html5.min.js"></script> <![endif]--> <title>Tinny Cropper</title> <link rel="stylesheet" href="style.css" type="text/css" /> <style> .container { position: absolute; top: 10%; left: 10%; right: 0; bottom: 0; } .action { width: 400px; height: 30px; margin: 10px 0; } .cropped>img { margin-right: 10px; } </style> </head> <body> <script src="../cropbox.js"></script> <div class="container"> <div class="imageBox"> <div class="thumbBox"></div> <div class="spinner" style="display: none">Loading...</div> </div> <div class="action"> <input type="file" id="file" style="float:left; width: 250px"> <input type="button" id="btnCrop" value="Crop" style="float: right"> <input type="button" id="btnZoomIn" value="+" style="float: right"> <input type="button" id="btnZoomOut" value="-" style="float: right"> </div> <div class="cropped"> </div> </div> <script type="text/javascript"> window.onload = function() { var options = { imageBox: '.imageBox', thumbBox: '.thumbBox', spinner: '.spinner', imgSrc: 'avatar.png' } var cropper; document.querySelector('#file').addEventListener('change', function(){ var reader = new FileReader(); reader.onload = function(e) { options.imgSrc = e.target.result; cropper = new cropbox(options); } reader.readAsDataURL(this.files[0]); this.files = []; }) document.querySelector('#btnCrop').addEventListener('click', function(){ var img = cropper.getDataURL() document.querySelector('.cropped').innerHTML += '<img src="'+img+'">'; }) document.querySelector('#btnZoomIn').addEventListener('click', function(){ cropper.zoomIn(); }) document.querySelector('#btnZoomOut').addEventListener('click', function(){ cropper.zoomOut(); }) }; </script> </body> </html>
css样式
.imageBox
{
position: relative;
height: 400px;
width: 400px;
border:1px solid #aaa;
background: #fff;
overflow: hidden;
background-repeat: no-repeat;
cursor:move;
}
.imageBox .thumbBox
{
position: absolute;
top: 50%;
left: 50%;
width: 200px;
height: 200px;
margin-top: -100px;
margin-left: -100px;
box-sizing: border-box;
border: 1px solid rgb(102, 102, 102);
box-shadow: 0 0 0 1000px rgba(0, 0, 0, 0.5);
background: none repeat scroll 0% 0% transparent;
}
.imageBox .spinner
{
position: absolute;
top: 0;
left: 0;
bottom: 0;
right: 0;
text-align: center;
line-height: 400px;
background: rgba(0,0,0,0.7);
}
js代码
/**
* Created by ezgoing on 14/9/2014.
*/
'use strict';
var cropbox = function(options){
var el = document.querySelector(options.imageBox),
obj =
{
state : {},
ratio : 1,
options : options,
imageBox : el,
thumbBox : el.querySelector(options.thumbBox),
spinner : el.querySelector(options.spinner),
image : new Image(),
getDataURL: function ()
{
var width = this.thumbBox.clientWidth,
height = this.thumbBox.clientHeight,
canvas = document.createElement("canvas"),
dim = el.style.backgroundPosition.split(' '),
size = el.style.backgroundSize.split(' '),
dx = parseInt(dim[0]) - el.clientWidth/2 + width/2,
dy = parseInt(dim[1]) - el.clientHeight/2 + height/2,
dw = parseInt(size[0]),
dh = parseInt(size[1]),
sh = parseInt(this.image.height),
sw = parseInt(this.image.width);
canvas.width = width;
canvas.height = height;
var context = canvas.getContext("2d");
context.drawImage(this.image, 0, 0, sw, sh, dx, dy, dw, dh);
var imageData = canvas.toDataURL('image/png');
return imageData;
},
getBlob: function()
{
var imageData = this.getDataURL();
var b64 = imageData.replace('data:image/png;base64,','');
var binary = atob(b64);
var array = [];
for (var i = 0; i < binary.length; i++) {
array.push(binary.charCodeAt(i));
}
return new Blob([new Uint8Array(array)], {type: 'image/png'});
},
zoomIn: function ()
{
this.ratio*=1.1;
setBackground();
},
zoomOut: function ()
{
this.ratio*=0.9;
setBackground();
}
},
attachEvent = function(node, event, cb)
{
if (node.attachEvent)
node.attachEvent('on'+event, cb);
else if (node.addEventListener)
node.addEventListener(event, cb);
},
detachEvent = function(node, event, cb)
{
if(node.detachEvent) {
node.detachEvent('on'+event, cb);
}
else if(node.removeEventListener) {
node.removeEventListener(event, render);
}
},
stopEvent = function (e) {
if(window.event) e.cancelBubble = true;
else e.stopImmediatePropagation();
},
setBackground = function()
{
var w = parseInt(obj.image.width)*obj.ratio;
var h = parseInt(obj.image.height)*obj.ratio;
var pw = (el.clientWidth - w) / 2;
var ph = (el.clientHeight - h) / 2;
el.setAttribute('style',
'background-image: url(' + obj.image.src + '); ' +
'background-size: ' + w +'px ' + h + 'px; ' +
'background-position: ' + pw + 'px ' + ph + 'px; ' +
'background-repeat: no-repeat');
},
imgMouseDown = function(e)
{
stopEvent(e);
obj.state.dragable = true;
obj.state.mouseX = e.clientX;
obj.state.mouseY = e.clientY;
},
imgMouseMove = function(e)
{
stopEvent(e);
if (obj.state.dragable)
{
var x = e.clientX - obj.state.mouseX;
var y = e.clientY - obj.state.mouseY;
var bg = el.style.backgroundPosition.split(' ');
var bgX = x + parseInt(bg[0]);
var bgY = y + parseInt(bg[1]);
el.style.backgroundPosition = bgX +'px ' + bgY + 'px';
obj.state.mouseX = e.clientX;
obj.state.mouseY = e.clientY;
}
},
imgMouseUp = function(e)
{
stopEvent(e);
obj.state.dragable = false;
},
zoomImage = function(e)
{
var evt=window.event || e;
var delta=evt.detail? evt.detail*(-120) : evt.wheelDelta;
delta > -120 ? obj.ratio*=1.1 : obj.ratio*=0.9;
setBackground();
}
obj.spinner.style.display = 'block';
obj.image.onload = function() {
obj.spinner.style.display = 'none';
setBackground();
attachEvent(el, 'mousedown', imgMouseDown);
attachEvent(el, 'mousemove', imgMouseMove);
attachEvent(document.body, 'mouseup', imgMouseUp);
var mousewheel = (/Firefox/i.test(navigator.userAgent))? 'DOMMouseScroll' : 'mousewheel';
attachEvent(el, mousewheel, zoomImage);
};
obj.image.src = options.imgSrc;
attachEvent(el, 'DOMNodeRemoved', function(){detachEvent(document.body, 'DOMNodeRemoved', imgMouseUp)});
return obj;
};
