图片自定义裁剪如何实现？本文主要介绍了jquery实现自定义图片裁剪功能，代码超级简单，易修改。下面跟着小编一起来看下吧，希望能帮助到大家。
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=$('<p 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=""><p id="photoCropBox-panel-box" style="position: relative;width: 100%;height: 100%;">' +
'<p 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"><p 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=""></p><p 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></p></p>' +
'</p></p>');
$('body').append(photoCropBox);
var _box=$('#photoCropBox-img');
var imgWidth=_box.find('img').width();
$('#photoCropBox-option span').css({
lineHeight:'30px',
background:'#000',
color:'#fff',
display:'inline-block',
paddingLeft:'20px',
paddingRight:'20px',
marginRight:'5px',
cursor:'pointer'
})
var cropBox=$('<p id="photoCropBox-cropBox" style="position: absolute;z-index: 5;cursor: Move;display: none">' +
'<p 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="">' +
'<p class="top line" style="width: 100%;height: 1px;top: 0;left: 0;"></p><p class="right line" style="height: 100%;width: 1px;top: 0;right: 0"></p>' +
'<p class="line bottom" style="width: 100%;height: 1px;bottom: 0px;left: 0"></p><p class="left line" style="height: 100%;width: 1px;top: 0;left: 0"></p></p>' +
'<p id="cropBoxLine2"><p class="left line2" style="height: 100%;width: 1px;top: 0;left: 0;cursor: w-resize"></p><p class="right line2" style="height: 100%;width: 1px;top: 0;right: 0;cursor: e-resize"></p><p class="top line2" style="width: 100%;height: 1px;top: 0;left: 0;cursor: n-resize;position: absolute"></p><p class="bottom line2" style="width: 100%;height: 1px;bottom: 0px;left: 0;cursor: s-resize"></p>' +
'<p class="left bot" style="left: -3px;top: 50%;margin-top: -4px;cursor: w-resize"></p><p class="right bot" style="right: -3px;top: 50%;margin-top: -4px;cursor: e-resize"></p><p class="bottom bot" style="bottom: -3px;left: 50%;margin-left: -4px;cursor: s-resize"></p><p class="top bot" style="top: -3px;left: 50%;margin-left: -4px;cursor: n-resize"></p>' +
'<p class="left-top bot" style="left: -3px;top: -3px;cursor: nw-resize"></p><p class="left-bottom bot" style="left: -3px;bottom: -3px;cursor: sw-resize"></p><p class="right-top bot" style="right: -3px;top: -3px;cursor: ne-resize"></p><p class="right-bottom bot"style="right: -3px;bottom: -3px;cursor: se-resize"></p></p></p>');
var screen=$('<p id="photoCropBox-bg" style="background: rgba(0,0,0,.5);position: absolute;left: 0;top: 0;width: 100%;height: 100%;z-index: 4;cursor: crosshair;display: none"></p>')
_box.append(cropBox);
_box.append(screen);
var _corp=$('#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)
},
});
})
})大家学会了吗？赶紧动手尝试一下吧。
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