本篇内容主要讲解“怎么用cropper.js和exif.js实现头像上传缩放裁剪旋转”，感兴趣的朋友不妨来看看。本文介绍的方法操作简单快捷，实用性强。下面就让小编来带大家学习“怎么用cropper.js和exif.js实现头像上传缩放裁剪旋转”吧!
做了一个头像上传的小功能，同时处理了ios竖着拍照图片旋转的问题。cropper.js（注意：cropper压缩版的js在手机版版缩放图片会有黑屏和图片飞了的bug，所以建议引入开发版本的cropper）依赖jquery，exif是用来获取拍照信息的，用于修复ios竖着拍照旋转的问题，我用的是amazeui框架，我在文件中也引入。
这是html文件
<!doctype html><html lang="zh"><head> <meta charset="UTF-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>cropper图片裁剪缩放</title> <link rel="stylesheet" href="css/amazeui.min.css"> <link rel="stylesheet" href="css/cropper.css"> <link rel="stylesheet" href="css/amazeui.cropper.css"></head><body> <div class="am-form-group"> <label>logo</label> <div class="am-cf"> <a href="javascript:;" id="up-img-touch" data-am-modal="{target: '#doc-modal-1'}"> <img src="picture-2.jpg" id="pic_img" > <input type="hidden" name="new_pic" id="new_pic" value=""> </a> </div> </div> <!--图片上传框--> <div class="am-popup up-frame-bj " id="doc-modal-1"> <div class="am-modal-dialog up-frame-parent up-frame-radius"> <div class="header_check header_setting"> <a href="javascript:;" class="iconfont" data-am-modal-close>关闭</a> <h2>上传</h2> </div> <div class="up-frame-body"> <div class="up-pre-main am-cf" > <div class="up-pre-before up-frame-radius"> <img alt="" src="" id="image"> </div> </div> <div class="upload_btn am-cf"> <div class="am-fl am-form-file"> <button type="button" class="am-btn">上传图片</button> <input type="file" id="inputImage"> </div> <div class="rotateimg"> <span οnclick="rotateimgleft()">左</span> <span οnclick="rotateimgright()">右</span> </div> <div class="am-fr"> <button type="button" class="am-btn" id="up-btn-ok" url="admin/user/upload.action">确定</button> </div> </div> </div> </div> </div></body><script src="js/jquery.min.js" charset="utf-8"></script><script src="js/amazeui.min.js" charset="utf-8"></script><script src="js/cropper.js" charset="utf-8"></script><script src="js/exif.js" charset="utf-8"></script><script src="js/custom_up_img.js" charset="utf-8"></script></html>这是js文件
$(function() { 'use strict'; // 初始化 var $image = $('#image'); $image.cropper({ aspectRatio:1/1, viewMode : 1, autoCropArea:0.8, dragMode:'move', cropBoxMovable:false, cropBoxResizable:false, zoomOnTouch:true, zoomable:true, movable:true, }); var $inputImage = $('#inputImage'); var URL = window.URL || window.webkitURL; var Orientation var rotate_num var blobURL; if (URL) { $inputImage.change(function () { var files = this.files; var file; if (files && files.length) { file = files[0]; if (/^image\/\w+$/.test(file.type)) { blobURL = URL.createObjectURL(file); $image.attr("src",blobURL) EXIF.getData(file, function() { EXIF.getAllTags(this); Orientation = EXIF.getTag(this, 'Orientation'); }); $image.one('built.cropper', function () { // Revoke when load complete URL.revokeObjectURL(blobURL); }).cropper('reset', true).cropper('replace', blobURL); $inputImage.val(''); } else { window.alert('Please choose an image file.'); } } }); } else { $inputImage.prop('disabled', true).parent().addClass('disabled'); } $('#up-btn-ok').on('click',function(){ var img_src=$image.attr("src"); if(img_src==""){ $('#my-alert').modal('open'); return false; } var url=$(this).attr("url"); var canvas=$("#image").cropper('getCroppedCanvas'); var cv_img = document.createElement("canvas"); var ctx = cv_img.getContext("2d"); var x = canvas.width/2; var y = canvas.height/2; cv_img.width =canvas.width; cv_img.height =canvas.width; ctx.clearRect(0,0, canvas.width, canvas.height);//先清掉画布上的内容 ctx.translate(x,y);//将绘图原点移到画布中点 if(Orientation == 6) { ctx.rotate(Math.PI/2); } else if(Orientation == 3) { ctx.rotate(-Math.PI/2); } else if(Orientation == 8) { ctx.rotate(Math.PI/1); } ctx.translate(-x,-y);//将画布原点移动 ctx.drawImage(canvas,0,0); var data=cv_img.toDataURL("image/jpeg"); $("#pic_img").attr("src",data) $('#new_pic').val($("#pic_img").attr("src")); $('#doc-modal-1').modal('close'); });});function rotateimgright() { $("#image").cropper('rotate', 90);}function rotateimgleft() { $("#image").cropper('rotate', -90);}function set_alert_info(content){ $("#alert_content").html(content);}到此，相信大家对“怎么用cropper.js和exif.js实现头像上传缩放裁剪旋转”有了更深的了解，不妨来实际操作一番吧！这里是编程网网站，更多相关内容可以进入相关频道进行查询，关注我们，继续学习！
