用于下载bk的书籍图片，下载下来之后需要自己用pdf软件合并
// ==UserScript==
// @name bk
// @version 0.4
// @author Fructose
// @match https://wk5.bookan.com.cn/*
// @grant GM_addStyle
// @require https://code.jquery.com/jquery-3.1.0.js
// @license MIT
// @description 用于下载bk的书籍图片，下载下来之后需要自己用pdf软件合并
// @namespace https://greasyfork.org/users/1261551
// ==/UserScript==
'use strict';
/* 用于页面添加下载按钮 */
GM_addStyle(`
#downloadMain { position: fixed; z-index: 999; right: 0; bottom: 20px; background: #fff; }
#downloadMain-bd { box-sizing: border-box; height: 60px; padding: 10px; border: 1px solid #ccc; }
#downloadMainBtn { font-size: 13px; line-height: 39px; display: inline-block; width: 60px; height: 40px; margin-left: -5px; text-align: center; text-decoration: none; color: #fff; background: #4d90fe; }
#zizhuPopupMainInput { display: inline-block; box-sizing: border-box; width: 210px; height: 40px; padding: 0 10px; border: 1px solid #ccc; outline: none; }
`);
// 添加内容
var smallCnt = `
<div id="downloadMain">
<input type="text" name="" placeholder="与真实页面的偏移量，没啥用填0" id="zizhuPopupMainInput" />
<a href="javascript:void(0);" id="downloadMainBtn">下载</a>
</div>`;
// 添加到 body
var odom = document.createElement("div");
odom.id = "downloadMain";
odom.innerHTML = smallCnt;
document.body.appendChild(odom);
/* 这是一个封装好的下载文件的函数 */
const downFile = (url, name, type) => {
return new Promise((resolve, reject) => {
fileAjax(url, function (xhr) {
downloadFile(xhr.response, name.concat(type));
resolve(); // 下载完成后解析Promise
}, {
responseType: 'blob'
}, reject);
});
};
function fileAjax(url, callback, options, reject) {
let xhr = new XMLHttpRequest();
xhr.open('get', url, true);
if (options.responseType) {
xhr.responseType = options.responseType;
}
xhr.onreadystatechange = function () {
if (xhr.readyState === 4 && xhr.status === 200) {
callback(xhr);
} else if (xhr.readyState === 4) {
reject(new Error('请求失败'));
}
};
xhr.send();
}
function downloadFile(content, filename) {
window.URL = window.URL || window.webkitURL;
let a = document.createElement('a');
let blob = new Blob([content]);
// 通过二进制文件创建url
let url = window.URL.createObjectURL(blob);
a.href = url;
a.download = filename;
a.click();
// 销毁创建的url
window.URL.revokeObjectURL(url);
}
/* 实现sleep函数，减慢速度 */
const sleep = (time) => {
return new Promise(resolve => setTimeout(resolve, time));
};
/* 将http链接追加上https */
const http2https = (http) => {
return http.slice(0, 4).concat("s", http.slice(4));
};
/* 以下为针对本页面的逻辑 */
/* 以下为针对本页面获取 提取该页面的图片地址、页数（不是页码）、#id */
const page = (type) => {
switch (type) {
case "src": return document.querySelector("img").src; break;
case "num": return document.querySelector("img").getAttribute("id").substr(6); break; // 获取到id后用substr取第6个字符以后的内容
case "id": return document.querySelector("img").id; break;
}
};
const imgID = document.querySelector("img");
const downloadedFiles = []; // 存储已下载文件名
const downloadStart = async () => {
const offset = Number(document.getElementById("zizhuPopupMainInput").value);
let currentPageNum = page("num");
while (currentPageNum >= 0) {
const fileName = `${String(currentPageNum - offset)}.jpg`;
console.log(`处理第 ${currentPageNum - offset} 页，文件名: ${fileName}`);
if (!downloadedFiles.includes(fileName)) {
console.log(`准备下载 ${fileName}`);
try {
await downFile(http2https(page("src")), fileName, ".jpg");
downloadedFiles.push(fileName); // 记录已下载的文件名
} catch (error) {
console.error("下载失败:", error);
}
} else {
console.log(`${fileName} 已经下载过，跳过`);
}
// 翻页
document.querySelector("div[class='page-wrapper']").click();
await sleep(4000); // 等待页面加载新的图片
// 更新当前页码
currentPageNum = page("num");
}
};
document.getElementById('downloadMainBtn').addEventListener('click', downloadStart); // 监听按钮是否被点击，如果点击则开始下载