js实现多张图片打包成zip
时间:2022-05-16 08:45:36|栏目:JavaScript代码|点击: 次
1、引入文件
<script src="https://cdn.bootcdn.net/ajax/libs/jquery/3.6.0/jquery.min.js"></script> <script src="https://cdn.bootcdn.net/ajax/libs/jszip/3.6.0/jszip.min.js"></script> <script src="https://cdn.bootcdn.net/ajax/libs/FileSaver.js/2.0.5/FileSaver.min.js"></script>
2、html页面
<button onclick="packageImages()">下载zip</button><span id="status"></span>
3、主要代码
function packageImages() { $('#status').text('处理中。。。。。') var imgsSrc = [] // https://dss0.bdstatic.com/70cFuHSh_Q1YnxGkpoWK1HF6hhy/it/u=2496571732,442429806&fm=26&gp=0.jpg // https://dss3.bdstatic.com/70cFv8Sh_Q1YnxGkpoWK1HF6hhy/it/u=2151136234,3513236673&fm=26&gp=0.jpg for (var i = 0; i < 1; i++) { imgsSrc.push('https://img.alicdn.com/bao/uploaded/i1/446338500/O1CN01npzdZ52Cf3A4cx8JG_!!0-item_pic.jpg_240x240.jpg') } var imgBase64 = [] //base64图片 var imageSuffix = [] //图片后缀 var zip = new JSZip() zip.file('readme.txt', '案件详情资料\n') var img = zip.folder('images') for (var i = 0; i < imgsSrc.length; i++) { var suffix = imgsSrc[i].substring(imgsSrc[i].lastIndexOf('.')) imageSuffix.push(suffix) getBase64(imgsSrc[i]).then( function (base64) { console.log(base64) imgBase64.push(base64.replace(/^data:image\/(png|jpg|jpeg);base64,/, "")) // 当所有图片转成base64执行图片压缩 if (imgsSrc.length == imgBase64.length) { for (var i = 0; i < imgsSrc.length; i++) { // 文件名 数据 img.file(i + imageSuffix[i], imgBase64[i], { base64: true, }) } zip.generateAsync({ type: 'blob' }).then(function (content) { console.log(1) // see FileSaver.js saveAs(content, 'images.zip') $('#status').text('处理完成。。。。。') }) } }, function (err) { console.log(err) //打印异常信息 } ) } } //传入图片路径,返回base64 function getBase64(img) { function getBase64Image(img, width, height) { //width、height调用时传入具体像素值,控制大小 ,不传则默认图像大小 var canvas = document.createElement('canvas') canvas.width = width ? width : img.width canvas.height = height ? height : img.height var ctx = canvas.getContext('2d') ctx.drawImage(img, 0, 0, canvas.width, canvas.height) var dataURL = canvas.toDataURL() return dataURL } var image = new Image() image.crossOrigin = 'Anonymous' image.src = img var deferred = $.Deferred() if (img) { image.onload = function () { deferred.resolve(getBase64Image(image)) //将base64传给done上传处理 } return deferred.promise() //问题要让onload完成后再return sessionStorage['imgTest'] } }
4、优化图片转base64的流程,提高zip的打包速度
function packageImages() { $('#status').text('处理中。。。。。') var imgsSrc = [] // https://dss0.bdstatic.com/70cFuHSh_Q1YnxGkpoWK1HF6hhy/it/u=2496571732,442429806&fm=26&gp=0.jpg // https://dss3.bdstatic.com/70cFv8Sh_Q1YnxGkpoWK1HF6hhy/it/u=2151136234,3513236673&fm=26&gp=0.jpg for (var i = 0; i < 1; i++) { imgsSrc.push('https://dss0.bdstatic.com/70cFuHSh_Q1YnxGkpoWK1HF6hhy/it/u=2496571732,442429806&fm=26&gp=0.jpg') } var imgBase64 = [] //base64图片 var imageSuffix = [] //图片后缀 var zip = new JSZip() zip.file('readme.txt', '案件详情资料\n') var img = zip.folder('images') for (var i = 0; i < imgsSrc.length; i++) { var suffix = imgsSrc[i].substring(imgsSrc[i].lastIndexOf('.')) imageSuffix.push(suffix) getBase64(imgsSrc[i], function (base64) { imgBase64.push(base64.replace(/^data:image\/(png|jpg|jpeg);base64,/, "")) if (imgsSrc.length == imgBase64.length) { for (var i = 0; i < imgsSrc.length; i++) { // 文件名 数据 img.file(i + imageSuffix[i], imgBase64[i], { base64: true, }) } zip.generateAsync({ type: 'blob' }).then(function (content) { console.log(1) // see FileSaver.js saveAs(content, 'images.zip') $('#status').text('处理完成。。。。。') }) } }) } } function getBase64(img, callback) { fetch(img).then( res => res.blob()) .then(res => { let fr = new FileReader();//https://developer.mozilla.org/zh-CN/docs/Web/API/FileReader fr.onload = function (e) { callback(e.target.result) }; fr.onerror = function () { console.log('读取错误!') }; fr.readAsDataURL(res);//如果是转文字,第二个参数可以使用编码 }) }
5、再优化,通过axios把图片转成base64
function packageImages() { $('#status').text('处理中。。。。。') var imgsSrc = [] // https://dss0.bdstatic.com/70cFuHSh_Q1YnxGkpoWK1HF6hhy/it/u=2496571732,442429806&fm=26&gp=0.jpg // https://dss3.bdstatic.com/70cFv8Sh_Q1YnxGkpoWK1HF6hhy/it/u=2151136234,3513236673&fm=26&gp=0.jpg for (var i = 0; i < 100; i++) { imgsSrc.push('https://dss0.bdstatic.com/70cFuHSh_Q1YnxGkpoWK1HF6hhy/it/u=2496571732,442429806&fm=26&gp=0.jpg') } handleBatchDownload(imgsSrc) } getFile = (url) => { return new Promise((resolve, reject) => { axios({ method: 'get', url, responseType: 'arraybuffer' }).then(data => { resolve(data.data) }).catch(error => { reject(error.toString()) }) }) }; // 批量下载 handleBatchDownload = async (selectImgList) => { const data = selectImgList; const zip = new JSZip() const promises = [] await data.forEach((item, idx) => { // console.log(item, idx) const promise = this.getFile(item).then(async (data) => { // 下载文件, 并存成ArrayBuffer对象 const arr_name = item.split("/"); let file_name = arr_name[arr_name.length - 1] // 获取文件名 // if (file_name.indexOf('.png') == -1) { // file_name = file_name + '.png' // } await zip.file(idx + '.png', data, { binary: true }) // 逐个添加文件 }) promises.push(promise) }) Promise.all(promises).then(() => { zip.generateAsync({ type: "blob" }).then(content => { // 生成二进制流 saveAs(content, "photo.zip") // 利用file-saver保存文件 $('#status').text('处理完成。。。。。') }) }) };
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