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java上传图片压缩包(js实现多张图片打包成zip)

时间:2022-01-28 01:28:52类别:编程学习

java上传图片压缩包

js实现多张图片打包成zip

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。。。。。')
            })
        })
    
    };
    
    
  • 以上就是js实现多张图片打包成zip的详细内容,更多关于js 图片打包成zip的资料请关注开心学习网其它相关文章!

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