第一种方法参考本站之前有人发的代码，增加了加载检测；
第二种方法来自去年的12306刷票脚本。
第一种方法：
function withjQuery(callback) { if(!(window.jQuery)) { var js = document.createElement('script'); js.setAttribute('src', 'https://dynamic.12306.cn/otsweb/js/common/jquery-1.4.2.min.js?version=5.47'); js.setAttribute('type', 'text/javascript'); js.onload = js.onreadystatechange = function() { if (!this.readyState || this.readyState === 'loaded' || this.readyState === 'complete') { if(callback && typeof callback === "function") { callback(); } js.onload = js.onreadystatechange = null; } }; document.getElementsByTagName('head')[0].appendChild(js); } } withjQuery( function() { $(function(){ alert("jQuery loaded"); })(); } );
第二种方法：
// ==UserScript== // @name 12306 Booking Assistant // @version 1.4.0 // @author zzdhidden@gmail.com // @namespace https://github.com/zzdhidden // @description 12306 订票助手之(自动登录，自动查票，自动订单) // @include *://dynamic.12306.cn/otsweb/* // @require https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js // ==https://www.jb51.net/UserScript== function withjQuery(callback, safe){ if(typeof(jQuery) == "undefined") { var script = document.createElement("script"); script.type = "text/javascript"; script.src = "https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"; if(safe) { var cb = document.createElement("script"); cb.type = "text/javascript"; cb.textContent = "jQuery.noConflict();(" + callback.toString() + ")(jQuery, window);"; script.addEventListener('load', function() { document.head.appendChild(cb); }); } else { var dollar = undefined; if(typeof($) != "undefined") dollar = $; script.addEventListener('load', function() { jQuery.noConflict(); $ = dollar; callback(jQuery, window); }); } document.head.appendChild(script); } else { setTimeout(function() { //Firefox supports callback(jQuery, typeof unsafeWindow === "undefined" ? window : unsafeWindow); }, 30); } } withjQuery(function($, window){ $(function() { alert("jQuery loaded"); })(); }, true);