jquery实现自定义图片裁剪功能【推荐】

1.自定义宽高效果

1.html 代码  index.html

<!DOCTYPE html>
<html lang="en">
<head>
 <meta charset="UTF-8">
 <title>Title</title>
 <script src="./jquery-1.12.4.min.js"></script>
</head>
<body>
<img class="source" src="./test2.jpg" alt="">
<img src="" class="target" alt="">
</body>
</html>　　

2.添加插件代码

(function ($) {
 $.fn.photoCrop=function (option) {
 var opt={
 img:'',
 fixedScale:9/5,
 isHead:null,
 maxWidth:'1400',
 maxHeight:'800',
 callBack:function () {}
 }
 opt=$.extend(opt,option);
 var _this=this;
 var imgSrc=opt.img ? opt.img:_this.attr('src');
 var photoCropBox=$('<div id="photoCropBox" style="position: fixed;width: 100%;height: 100%;top: 0;left: 0;background: rgba(0,0,0,0.5);z-index: 99999;padding: 20px;">' +
 '<canvas id="cropCanvas" style="position: absolute;opacity:1;left: 0;top: 0;z-index: 100"></canvas><img id="dataImg" src="'+imgSrc+'" style="opacity: 0;position: absolute" alt=""><div id="photoCropBox-panel-box" style="position: relative;width: 100%;height: 100%;">' +
 '<div id="photoCropBox-panel" style="opacity:0;background: #eee;border-radius: 5px;max-width: '+opt.maxWidth+'px;max-height: '+opt.maxHeight+'px;position: absolute;text-align: center"><div id="photoCropBox-img" style="margin: 40px 60px 20px;display: inline-block;position: relative">' +
 '<img src="'+imgSrc+'" style="max-width: 100%;display: block;max-height: 100%;max-height: '+(opt.maxHeight-110)+'px;" alt=""></div><div id="photoCropBox-option" style="text-align: right;padding-right: 50px;padding-bottom: 20px;position: relative;z-index: 2"><span id="photoCropBox-end">裁剪</span><span id="photoCropBox-start">手动裁剪</span><span id="photoCropBox-cancel">取消</span></div></div>' +
 '</div></div>');
 $('body').append(photoCropBox);
 var _box=$('#photoCropBox-img');
 var imgWidth=_box.find('img').width();
 $('#photoCropBox-option span').css({
 lineHeight:'30px',
 background:'#000',
 color:'#fff',
 display:'inline-block',
 paddingLeft:'20px',
 paddingRight:'20px',
 marginRight:'5px',
 cursor:'pointer'
 })
 var cropBox=$('<div id="photoCropBox-cropBox" style="position: absolute;z-index: 5;cursor: Move;display: none">' +
 '<div id="cropBoxLine" style="overflow: hidden;position: absolute;width: 100%;height: 100%;">' +
 '<img src="'+imgSrc+'" style="display: block;width: '+_box.find('img').width()+'px;position: absolute;max-height: none;max-width: none" alt="">' +
 '<div class="top line" style="width: 100%;height: 1px;top: 0;left: 0;"></div><div class="right line" style="height: 100%;width: 1px;top: 0;right: 0"></div>' +
 '<div class="line bottom" style="width: 100%;height: 1px;bottom: 0px;left: 0"></div><div class="left line" style="height: 100%;width: 1px;top: 0;left: 0"></div></div>' +
 '<div id="cropBoxLine2"><div class="left line2" style="height: 100%;width: 1px;top: 0;left: 0;cursor: w-resize"></div><div class="right line2" style="height: 100%;width: 1px;top: 0;right: 0;cursor: e-resize"></div><div class="top line2" style="width: 100%;height: 1px;top: 0;left: 0;cursor: n-resize;position: absolute"></div><div class="bottom line2" style="width: 100%;height: 1px;bottom: 0px;left: 0;cursor: s-resize"></div>' +
 '<div class="left bot" style="left: -3px;top: 50%;margin-top: -4px;cursor: w-resize"></div><div class="right bot" style="right: -3px;top: 50%;margin-top: -4px;cursor: e-resize"></div><div class="bottom bot" style="bottom: -3px;left: 50%;margin-left: -4px;cursor: s-resize"></div><div class="top bot" style="top: -3px;left: 50%;margin-left: -4px;cursor: n-resize"></div>' +
 '<div class="left-top bot" style="left: -3px;top: -3px;cursor: nw-resize"></div><div class="left-bottom bot" style="left: -3px;bottom: -3px;cursor: sw-resize"></div><div class="right-top bot" style="right: -3px;top: -3px;cursor: ne-resize"></div><div class="right-bottom bot"style="right: -3px;bottom: -3px;cursor: se-resize"></div></div></div>');
 var screen=$('<div id="photoCropBox-bg" style="background: rgba(0,0,0,.5);position: absolute;left: 0;top: 0;width: 100%;height: 100%;z-index: 4;cursor: crosshair;display: none"></div>')
 _box.append(cropBox);
 _box.append(screen);
 var _corp=$('#photoCropBox-cropBox');
 var cropBoxLine=$('#cropBoxLine');
 setTimeout(function () {
 console.log(imgWidth)
 cropBoxLine.find('img').css('width',_box.find('img').width()+'px')
 },20)
 if(opt.isHead){
 cropBoxLine.css({borderRadius:'100%'})
 }
 $('#photoCropBox-cropBox .line,#photoCropBox-cropBox .line2').css({
 background:'url(./img/Jcrop.gif)',
 position:'absolute',
 opacity:.5
 })
 $('#photoCropBox-cropBox .bot').css({
 background:'rgba(0,0,0,0.5)',
 position:'absolute',
 width:7,
 height:7,
 border:'1px #999 solid'
 })
 setTimeout(function () {
 init();
 },10)
 $(window).on('resize',function () {
 setPosition();
 })
 $('#photoCropBox-cancel').on('click',function () {
 closeBox();
 })
 $('#photoCropBox-bg').on('mousedown',function (e) {
 if(opt.fixedScale) return //固定
 $('#cropBoxLine2').hide();
 var _this=$(this);
 var _sx=e.pageX,_sy=e.pageY;
 var _tx=_this.offset().left;
 var _ty=_this.offset().top;
 $(document).on('mousemove',function (e) {
 e.preventDefault();
 var _ex=e.pageX,_ey=e.pageY;
 getPosition(_ex,_ey,_ty,_tx,_sx,_sy,_this)
 })
 $(document).on('mouseup',function () {
 $(document).unbind('mousemove');
 $('#cropBoxLine2').show();
 })
 })
 var lock=false;
 _corp.on('mousedown',function (e) {
 if(lock){return}
 var _sx=e.pageX,_sy=e.pageY;
 var pW=$('#photoCropBox-bg').width(),pH=$('#photoCropBox-bg').height();
 var _this=$(this),_thisX=parseInt(_this.css('left')),_thisY=parseInt(_this.css('top')),_thisW=parseInt(_this.css('width')),_thisH=parseInt(_this.css('height'));
 $(document).on('mousemove',function (e) {
 e.preventDefault();
 var _ex=e.pageX,_ey=e.pageY;
 var _x=_ex-_sx,_y=_ey-_sy;
 _x+=_thisX;_y+=_thisY;
 if(_x<0) _x=0;
 if(_y<0) _y=0;
 if(_y>pH-_thisH) _y=pH-_thisH;
 if(_x>pW-_thisW) _x=pW-_thisW;
 resizeCropBox("","",_y,_x,true)
 })
 $(document).on('mouseup',function () {
 $(document).unbind('mousemove');
 })
 })
 //控制大小
 $('#cropBoxLine2 .bot').on("mousedown",function (e) {
 lock=true;
 var _esx=e.pageX,_esy=e.pageY;
 var _that=$(this);
 var _this=$('#photoCropBox-bg');
 var _tx=_this.offset().left;
 var _ty=_this.offset().top;
 var _sx=_corp.offset().left,_sy=_corp.offset().top;//裁剪框
 if(_that.hasClass('right-top')) _sy+=_corp.height();
 if(_that.hasClass('left-top')){
 _sy+=_corp.height();
 _sx+=_corp.width();
 }
 if(_that.hasClass('left-bottom')) _sx+=_corp.width();
 $(document).on('mousemove',function (e) {
 e.preventDefault();
 var _ex=e.pageX,_ey=e.pageY;
 if(opt.fixedScale){
 _ey=(_ex-_esx)/opt.fixedScale+_esy;
 if(_that.hasClass('right-top') || _that.hasClass('left-bottom')){
 _ey=(_esx-_ex)/opt.fixedScale+_esy;
 }
 }
 getPosition(_ex,_ey,_ty,_tx,_sx,_sy,_this)
 })
 $(document).on('mouseup',function () {
 $(document).unbind('mousemove');
 lock=false;
 })
 }) $('#cropBoxLine2 .left,#cropBoxLine2 .top,#cropBoxLine2 .right,#cropBoxLine2 .bottom').on('mousedown',function (e) {
 if(opt.fixedScale) return //固定
 lock=true;
 var _that=$(this);
 var _this=$('#photoCropBox-bg');
 var _tx=_this.offset().left;//
 var _ty=_this.offset().top;
 var _sx=_corp.offset().left,_sy=_corp.offset().top;
 var ch=_corp.height(),cw=_corp.width();
 if(_that.hasClass('top')){
 _sy+=ch;
 }else if(_that.hasClass('left')) {
 _sx+=cw;
 }
 $(document).on('mousemove',function (e) {
 e.preventDefault();
 var _ex=e.pageX,_ey=e.pageY;
 if(_that.hasClass('top') || _that.hasClass('bottom')){
 if(!(_ey-_sy>0)){
 var _x=_sx-_tx,_y=_ey-_ty,_w=cw,_h=-(_ey-_sy);
 if(_y<0) {_y=0;_h=_sy-_ty;}
 }else{
 var _x=_sx-_tx,_y=_sy-_ty,_w=cw,_h=_ey-_sy;
 if(_h>_this.height()-_y) _h=_this.height()-_y;
 }
 }else {
 if(_ex-_sx>0 && _ey-_sy>0){
 var _x=_sx-_tx,_y=_sy-_ty,_w=_ex-_sx,_h=ch;
 if(_w>_this.width()-_x) _w=_this.width()-_x;
 }else if(!(_ex-_sx>0) && _ey-_sy>0){
 var _x=_ex-_tx,_y=_sy-_ty,_w=-(_ex-_sx),_h=ch;
 if(_x<0) {_x=0;_w=_sx-_tx;}
 }
 }
 resizeCropBox(_w,_h,_y,_x);
 })
 $(document).on('mouseup',function () {
 $(document).unbind('mousemove');
 lock=false;
 })
 })
 $('#photoCropBox-start').on('click',function () {
 _corp.css('display','block')
 $('#photoCropBox-bg').css('display','block')
 })
 $('#photoCropBox-end').on('click',function () {
 getImage()
 closeBox()
 })
 function init() {
 setPosition()
 if(opt.fixedScale){
 if((_box.height()-_box.width()/opt.fixedScale/2)<0){
 resizeCropBox(_box.height()*opt.fixedScale,_box.height(),0,(_box.width()-_box.height()*opt.fixedScale)/2)
 }else {
 resizeCropBox(_box.width()/2,_box.width()/opt.fixedScale/2,(_box.height()-_box.width()/opt.fixedScale/2)/2,_box.width()/4)
 }
 }else {
 resizeCropBox(_box.width()/2,_box.height()/2,_box.height()/4,_box.width()/4)
 }
 if(opt.fixedScale) {
 $('.bot.top,.bot.left,.bot.bottom,.bot.right').remove();//固定
 }
 }
 function setPosition() {
 $('#photoCropBox-panel').css({
 top:($('#photoCropBox-panel-box').height()-$('#photoCropBox-panel').height())/2+'px',
 left:($('#photoCropBox-panel-box').width()-$('#photoCropBox-panel').width())/2+'px',
 opacity:1
 })
 }
 //结束x,y 背景x,y
 function getPosition(_ex,_ey,_ty,_tx,_sx,_sy,_this) {
 if(_ex-_sx>0 && _ey-_sy>0){
 var _x=_sx-_tx,_y=_sy-_ty,_w=_ex-_sx,_h=_ey-_sy;
 if(_w>_this.width()-_x) _w=_this.width()-_x;
 if(_h>_this.height()-_y) _h=_this.height()-_y;
 }else if(!(_ex-_sx>0) && _ey-_sy>0){
 var _x=_ex-_tx,_y=_sy-_ty,_w=-(_ex-_sx),_h=_ey-_sy;
 if(_x<0) {_x=0;_w=_sx-_tx;}
 if(_h>_this.height()-_y) _h=_this.height()-_y;
 }else if(!(_ex-_sx>0) && !(_ey-_sy>0)){
 var _x=_ex-_tx,_y=_ey-_ty,_w=-(_ex-_sx),_h=-(_ey-_sy);
 if(_x<0) {_x=0;_w=_sx-_tx;}
 if(_y<0) {_y=0;_h=_sy-_ty;}
 }else if(_ex-_sx>0 && !(_ey-_sy>0)){
 var _x=_sx-_tx,_y=_ey-_ty,_w=_ex-_sx,_h=-(_ey-_sy);
 if(_y<0) {_y=0;_h=_sy-_ty;}
 if(_w>_this.width()-_x) _w=_this.width()-_x;
 }
 if(opt.fixedScale){
 if(_w/opt.fixedScale>_h){
 _w=_h*opt.fixedScale
 }else if (_w<opt.fixedScale*_h){
 _h=_w/opt.fixedScale
 }
 }
 resizeCropBox(_w,_h,_y,_x);
 }
 var c=document.getElementById("cropCanvas");
 var ctx=c.getContext("2d");
 var img=$('#dataImg');
 function getImage() {
 var scale=$('#photoCropBox-img').width()/$('#dataImg').width();
 var sx=parseInt(_corp.css('left'))/scale;
 var sy=parseInt(_corp.css('top'))/scale;
 var swidth=parseInt(_corp.css('width'))/scale;
 var sheight=parseInt(_corp.css('height'))/scale;
 var c_img = new Image;
 c_img.onload = function () {
 ctx.drawImage(c_img,sx,sy,swidth,sheight,0,0,swidth,sheight);
 var url=c.toDataURL("image/jpeg");
 opt.callBack(url);
 };
 c_img.crossOrigin = 'anonymous'; //可选值：anonymous，*
 c_img.src = imgSrc
 c.width = swidth;
 c.height = sheight;
 }
 //宽，高,top,left,m-是否是拖拽
 function resizeCropBox(w,h,t,l,m) {
 _corp.css(prefix()+'transition','all 0s');
 if(!m){
 _corp.css({
 width:w,
 height:h,
 top:t+'px',
 left:l+'px'
 })
 }else {
 _corp.css({
 top:t+'px',
 left:l+'px'
 })
 }
 cropBoxLine.find('img').css({
 top:-t+'px',
 left:-l+'px'
 })
 }
 function closeBox() {
 $('#photoCropBox').remove();
 }
 function prefix() {
 var prefixes=['','-ms-','-moz-','-webkit-','-o-'],i=0;
 while (i < prefixes.length){
 if($('body').css(prefixes[i]+'transition')){
 return prefixes[i];
 }
 i++;
 }
 }
 }
 })(jQuery)　

3.绑定代码

$(function () {
 $('.source').on('click',function () {
 $(this).photoCrop({
 fixedScale:false,
 isHead:false,
 callBack:function(url){
 $('.target').attr('src',url)
 },
 });
 })

 })

2.宽高比例固定效果

代码：

$(function () {
 $('.source').on('click',function () {
 $(this).photoCrop({
 fixedScale:5/6,
 isHead:false,
 callBack:function(url){
 $('.target').attr('src',url)
 },
 });
 })
 })

3.头像裁剪效果

代码：

$(function () {
 $('.source').on('click',function () {
 $(this).photoCrop({
 fixedScale:1,
 isHead:true,
 callBack:function(url){
 $('.target').attr('src',url)
 },
 });
 })
 })

以上代码易修改，大家可以自行扩展。希望本文的内容对大家的学习或者工作能带来一定的帮助，同时也希望多多支持我们！