jsPDF 实现 Google 云端硬盘只读 PDF 文件下载导出

背景

https://www.savemyexams.co.uk

蜜汁刷题网站，会员简直就是在抢钱
好不容易搞了个教师折扣，试卷资源还不能下载…
本方法适用于 Google Drive 被设置为 Read Only 的 PDF 文件的下载导出

代码

/* 
    Via https://codingcat.codes/2019/01/09/download-view-protected-pdf-google-drive-js-code/
    If the images are not complete, try zooming the page to get the full image.
    1. Open Developer Tools on separate window and choose the Console tab
    2. Paste the code below (and hit enter)
*/

let jspdf = document.createElement("script");
 
jspdf.onload = function () {
 
    let pdf = new jsPDF();
    let elements = document.getElementsByTagName("img");
    for (let i in elements) {
        let img = elements[i];
        if (!/^blob:/.test(img.src)) {
            continue;
        }
        let can = document.createElement('canvas');
        let con = can.getContext('2d');
        can.width = img.width;
        can.height = img.height;
        con.drawImage(img, 0, 0);
        let imgData = can.toDataURL("image/jpeg", 1.0);
        pdf.addImage(imgData, 'JPEG', 0, 0);
        pdf.addPage();
    }

    pdf.save(document.title.split('.pdf - ')[0]+".pdf");
};
 
jspdf.src = 'https://cdn.bootcss.com/jspdf/1.5.3/jspdf.debug.js';
document.body.appendChild(jspdf);

↑ JavaScript 代码

注意

原代码来自 https://codingcat.codes/2019/...
打开浏览器开发者工具(单窗口打开)选择 Console / 控制台
复制代码，回车执行
若是图片绘制不完整，尝试缩放浏览器页面