- 军军小站|张军博客

JavaScript 的性能优化：加载和执行

概览无论当前JavaScript代码是内嵌还是在外链文件中，页面的下载和渲染都必须停下来等待脚本执行完成。JavaScript执行过程耗时越久，浏览器等待响应用户输入的时间就越长。浏览器在下载和执行脚本时出现阻塞的原因在于，脚本可能会改变页面或JavaScript的命名空间，它们对后面页面内容造成影响。一个典型的例子就是在页面中使用document.write()。例如清单1清单1JavaScript代码内嵌示例Sou</span> <p class="auth-span"> <span class="muted"><i class="fa fa-user"></i><span class="zj-icon-text">系统</span></span> <span class="muted"><i class="fa fa-clock-o"></i><span class="zj-icon-text">2019-08-29 22:50:45</span></span> <span class="muted"><i class="fa fa-eye"></i><span class="zj-icon-text">3221</span></span>  </p> </article><article class="excerpt"> <header> <a title="编程技术" class="label label-important zj-del-target" href="/category/30">编程技术<i class="label-arrow"></i></a> <h2> <a class="zj-titles zj-del-target" href="/article/14931" title="JS 文本输入框放大镜效果" target="_blank" onclick="return recordId('',)">JS 文本输入框放大镜效果 </a> </h2> </header> <div class="focus"> <a class="zj-del-target" href="/article/14931" target="_blank"><img style="width: 200px; height: 123px;" class="thumb" src="/Public/static/images/article/7.jpg" alt="" title=""></a> </div> <span class="note" onclick="if (jq.browser.versions.mobile) {window.location.href='/article/14931';}else{window.open('/article/14931');}" style="cursor: pointer;">JS文本输入框放大镜效果今天下午研究了下"文本输入框放大镜效果"当然KISSY官网也有这种组件请看kissydemo其实这种效果对于很多童鞋来说应该并不陌生！我今年最早也是在12306官网抢票中添加联系人要填写电话号码中看到这种效果！如下图所示：所以今天下午也就研究下这个，特此分享出来给大家！也做了一个简单的DEMOjSFiddle链接地址如下：JSFiddle链接：想要查看效果！请轻轻的点击我！基本原理：其实基本原理也很简单！通过JS不断的监听输入框值的</span> <p class="auth-span"> <span class="muted"><i class="fa fa-user"></i><span class="zj-icon-text">系统</span></span> <span class="muted"><i class="fa fa-clock-o"></i><span class="zj-icon-text">2019-08-29 22:22:01</span></span> <span class="muted"><i class="fa fa-eye"></i><span class="zj-icon-text">3221</span></span>  </p> </article><article class="excerpt"> <header> <a title="Javascript" class="label label-important zj-del-target" href="/category/66">Javascript<i class="label-arrow"></i></a> <h2> <a class="zj-titles zj-del-target" href="/article/12199" title="微软新推TypeScript取代JavaScript" target="_blank" onclick="return recordId('',)">微软新推TypeScript取代JavaScript </a> </h2> </header> <div class="focus"> <a class="zj-del-target" href="/article/12199" target="_blank"><img style="width: 200px; height: 123px;" class="thumb" src="/Public/static/images/article/7.jpg" alt="" title=""></a> </div> <span class="note" onclick="if (jq.browser.versions.mobile) {window.location.href='/article/12199';}else{window.open('/article/12199');}" style="cursor: pointer;">微软新推TypeScript取代JavaScriptTypeScript是一个应用程序级的JavaScript开发语言。TypeScript是JavaScript的超集，可以编译成纯JavaScript。TypeScript跨浏览器、跨操作系统、跨主机，开源。主页：http://www.typescriptlang.org/StartsfromJavaScript,EndswithJavaScriptTypeScript遵循JavaScript的语法和语义</span> <p class="auth-span"> <span class="muted"><i class="fa fa-user"></i><span class="zj-icon-text">系统</span></span> <span class="muted"><i class="fa fa-clock-o"></i><span class="zj-icon-text">2019-08-12 09:30:13</span></span> <span class="muted"><i class="fa fa-eye"></i><span class="zj-icon-text">3221</span></span>  </p> </article><article class="excerpt"> <header> <a title="Javascript" class="label label-important zj-del-target" href="/category/66">Javascript<i class="label-arrow"></i></a> <h2> <a class="zj-titles zj-del-target" href="/article/11068" title="(IBM)最大限度利用 JavaScript 和 Ajax 性能" target="_blank" onclick="return recordId('',)">(IBM)最大限度利用 JavaScript 和 Ajax 性能 </a> </h2> </header> <div class="focus"> <a class="zj-del-target" href="/article/11068" target="_blank"><img style="width: 200px; height: 123px;" class="thumb" src="/Public/static/images/article/1.jpg" alt="" title=""></a> </div> <span class="note" onclick="if (jq.browser.versions.mobile) {window.location.href='/article/11068';}else{window.open('/article/11068');}" style="cursor: pointer;">简介在web早期，优化web页面的性能通常意味着避免了使用不必要的HTML标记，将JavaScript代码量控制到最小，并尽量减小所有图片文件大小，否则上网冲浪者会走开去泡杯咖啡来等待页面加载。web各个方面的改进也意味着我们现在面临新的性能考虑。尽管DSL和宽带为很多人提供了对Internet上更多内容的高速访问，我们对加载时间和响应的期望也在发展，希望在页面上执行操作后能立刻得到结果。AsynchronousJavaScriptandXML(Ajax)</span> <p class="auth-span"> <span class="muted"><i class="fa fa-user"></i><span class="zj-icon-text">系统</span></span> <span class="muted"><i class="fa fa-clock-o"></i><span class="zj-icon-text">2019-08-12 09:29:30</span></span> <span class="muted"><i class="fa fa-eye"></i><span class="zj-icon-text">3221</span></span>  </p> </article><article class="excerpt"> <header> <a title="编程技术" class="label label-important zj-del-target" href="/category/30">编程技术<i class="label-arrow"></i></a> <h2> <a class="zj-titles zj-del-target" href="/article/15211" title="利用BeanUtils在对象间复制属性" target="_blank" onclick="return recordId('',)">利用BeanUtils在对象间复制属性 </a> </h2> </header> <div class="focus"> <a class="zj-del-target" href="/article/15211" target="_blank"><img style="width: 200px; height: 123px;" class="thumb" src="/Public/static/images/article/13.jpg" alt="" title=""></a> </div> <span class="note" onclick="if (jq.browser.versions.mobile) {window.location.href='/article/15211';}else{window.open('/article/15211');}" style="cursor: pointer;">commons-beanutils是jakartacommons子项目中的一个软件包，其主要目的是利用反射机制对JavaBean的属性进行处理。我们知道，一个JavaBean通常包含了大量的属性，很多情况下，对JavaBean的处理导致大量get/set代码堆积，增加了代码长度和阅读代码的难度（你的薪水按代码行数计算？那千万别让老板看到此帖哦）BeanUtils是这个包里比较常用的一个工具类，这里只介绍它的copyProperties()方法。该方法定义如</span> <p class="auth-span"> <span class="muted"><i class="fa fa-user"></i><span class="zj-icon-text">系统</span></span> <span class="muted"><i class="fa fa-clock-o"></i><span class="zj-icon-text">2019-08-29 22:25:30</span></span> <span class="muted"><i class="fa fa-eye"></i><span class="zj-icon-text">3220</span></span>  </p> </article><div class="pagination" style="display:;"> <ul><li><a href="/search/column/1/p/1">首页</a></li> <li class="prev-page"><a href="/search/column/1/p/189">上一页</a></li> <li><a href="/search/column/1/p/188">188</a></li><li><a href="/search/column/1/p/189">189</a></li><li class="active"><span>190</span></li><li><a href="/search/column/1/p/191">191</a></li><li><a href="/search/column/1/p/192">192</a></li> <li class="next-page"><a href="/search/column/1/p/191">下一页</a></li> <li><a href="/search/column/1/p/2923">末页</a></li> <li><span>共 2923页,共29230条</span></li> </ul> </div> </div> </div>   <style type="text/css"> .d_postlist .text { /* height: 30px; */ display: block; /* height: 100%; */ font-size:14px !important; width:85%; } .zj-dynamic-info li{ margin: 10px 3px; } .zj-dynamic-info .zj-a{ color: blue; cursor: pointer; } </style> <aside class="sidebar"> <div class="widget d_postlist"> <div class="title"> <h2>站内搜索</h2> </div> <ul> <li><div class="zj-search-box zj-pc-search-box"> <form class="searchform themeform" role="form" action="/search" method="get"> <input style="font-size: 120%; margin-top: 10px;" type="ext" class="search" name="search_word" placeholder="搜索从这里开始..." value=""> <i class="fa fa-search"></i> <button class="btn btn-primary" type="button" style="margin-left: -4px;height: 36px !important;"> <span class="zj-icon-text">搜索</span> </button> </form> </div></li> </ul> </div>    <div class="widget d_postlist"> <div class="title"> <h2>加入交流</h2> </div> <ul> <li class="zj-no-wx-app"><a target="_blank" href="//shang.qq.com/wpa/qunwpa?idkey=f6d1df60dbb7ebc94c2c8a67b1e094e1e90677df1e943d9547d425b81bb218a5"><span style="margin-right: 10px;" class="thumbnail"><img style="max-height: 100%;" src="/Public/static/images/qq-qun.png" alt=""></span><span class="text">1. 手机QQ扫左侧二维码</span><span class="text">2. 搜Q群：542395358</span> <span class="text">3. 点击<img style="cursor: pointer;" onclick="window.open('//shang.qq.com/wpa/qunwpa?idkey=f6d1df60dbb7ebc94c2c8a67b1e094e1e90677df1e943d9547d425b81bb218a5');" border="0" src="//pub.idqqimg.com/wpa/images/group.png" alt="张军网站共享资料群" title="张军网站共享资料群"> </span></a></li> <li class="zj-no-wx-app"><a target="_blank" href="//shang.qq.com/wpa/qunwpa?idkey=29dfc8d27e6e13276b9ea9848e3a211c076e130376a7b6ef380ffcc967e8a1fc"><span style="margin-right: 10px;" class="thumbnail"><img style="max-height: 100%;" src="/Public/static/images/qq-qun.png" alt=""></span><span class="text">1. 手机QQ扫左侧二维码</span><span class="text">2. 搜Q群：922215567</span> <span class="text">3. 点击<img style="cursor: pointer;" onclick="window.open('//shang.qq.com/wpa/qunwpa?idkey=29dfc8d27e6e13276b9ea9848e3a211c076e130376a7b6ef380ffcc967e8a1fc');" border="0" src="//pub.idqqimg.com/wpa/images/group.png" alt="java技术沟通群" title="java技术沟通群"> </span></a></li> <li><a target="_blank" href="javascript:void(0)" style="cursor: text;"><span style="margin-right: 10px;" class="thumbnail"><img style="max-height: 100%;" src="/Public/static/images/wx-gzh.jpg" alt="关注企业微信公众号"></span><span class="text">1.手机微信扫左侧二维码 </span><span class="text">2. 微信中搜索：上海加盾信息科技有限公司</span></a></li> <li><a target="_blank" href="javascript:void(0)" style="cursor: text;"><span style="margin-right: 10px;" class="thumbnail"><img style="max-height: 100%;" src="/Public/static/images/wx-app-zhangjunbk.jpg" alt="关注军军小站|张军博客小程序"></span><span class="text">1.手机微信扫左侧二维码 </span><span class="text">2. 微信搜索小程序：张军博客 </span></a></li> <li><a target="_blank" href="javascript:void(0)" style="cursor: text;"><span style="margin-right: 10px;" class="thumbnail"><img style="max-height: 100%;" src="/Public/static/images/wx-app-shanghaijiadun.jpg" alt="关注企业微信小程序"></span><span class="text">1.手机微信扫左侧二维码 </span><span class="text">2. 微信搜索小程序：上海加盾信息科技有限公司</span></a></li> <li><a target="_blank" href="javascript:void(0)" style="cursor: text;"><span style="margin-right: 10px;" class="thumbnail"><img style="max-height: 100%;" src="/Public/static/images/dingding.jpg" alt="关注企业钉钉"></span><span class="text">关注企业钉钉 </span></a></li> <li><a target="_blank" href="javascript:void(0)" style="cursor: text;"><span style="margin-right: 10px;" class="thumbnail"><img style="max-height: 100%;" src="/Public/static/images/qywx-my.png" alt="关注企业微信"></span><span class="text">关注企业微信 </span></a></li> <li><a target="_blank" href="javascript:void(0)" style="cursor: text;"><span style="margin-right: 10px;" class="thumbnail"><img style="max-height: 100%;" src="/Public/static/images/wx.zhangjunbk.com.png" alt="微信扫一扫添加张军网站微信群"></span><span class="text">微信扫一扫添加张军网站微信群 </span></a></li> <li><a target="_blank" href="javascript:void(0)" style="cursor: text;"><span style="margin-right: 10px;" class="thumbnail"><img style="max-height: 100%;" src="/Public/static/images/my-wx.png" alt="添加我为微信好友"></span><span class="text">微信扫一扫加我为好友 </span></a></li> </ul> </div>  <div class="widget d_tag"> <div class="title"> <h2>标签云</h2> </div> <div class="d_tags"> <a title="金融业务" href="/tag/37" onclick="return recordId('tid',37)">金融业务 (4)</a><a title="教育资料" href="/tag/39" onclick="return recordId('tid',39)">教育资料 (10)</a><a title="Java" href="/tag/41" onclick="return recordId('tid',41)">Java (901)</a><a title="C++" href="/tag/42" onclick="return recordId('tid',42)">C++ (86)</a><a title="C#" href="/tag/43" onclick="return recordId('tid',43)">C# (215)</a><a title="Python" href="/tag/44" onclick="return recordId('tid',44)">Python (9022)</a><a title="Oracle" href="/tag/45" onclick="return recordId('tid',45)">Oracle (911)</a><a title="SqlServer" href="/tag/46" onclick="return recordId('tid',46)">SqlServer (681)</a><a title="MySql" href="/tag/47" onclick="return recordId('tid',47)">MySql (600)</a><a title="DB2" href="/tag/48" onclick="return recordId('tid',48)">DB2 (33)</a><a title="PostgreSql" href="/tag/49" onclick="return recordId('tid',49)">PostgreSql (23)</a><a title="Tomcat" href="/tag/50" onclick="return recordId('tid',50)">Tomcat (825)</a><a title="Weblogic" href="/tag/51" onclick="return recordId('tid',51)">Weblogic (12)</a><a title="Windows" href="/tag/52" onclick="return recordId('tid',52)">Windows (214)</a><a title="Linux" href="/tag/53" onclick="return recordId('tid',53)">Linux (647)</a><a title="VMware" href="/tag/54" onclick="return recordId('tid',54)">VMware (32)</a><a title="Ubuntu" href="/tag/55" onclick="return recordId('tid',55)">Ubuntu (194)</a><a title="ASP.NET" href="/tag/56" onclick="return recordId('tid',56)">ASP.NET (198)</a><a title="Android" href="/tag/57" onclick="return recordId('tid',57)">Android (681)</a><a title="IOS" href="/tag/58" onclick="return recordId('tid',58)">IOS (75)</a><a title="Hive" href="/tag/59" onclick="return recordId('tid',59)">Hive (45)</a><a title="Hadoop" href="/tag/60" onclick="return recordId('tid',60)">Hadoop (50)</a><a title="Hbase" href="/tag/61" onclick="return recordId('tid',61)">Hbase (9)</a><a title="Spark" href="/tag/62" onclick="return recordId('tid',62)">Spark (4)</a><a title="redis" href="/tag/63" onclick="return recordId('tid',63)">redis (78)</a><a title="PHP" href="/tag/64" onclick="return recordId('tid',64)">PHP (145)</a><a title="Jquery" href="/tag/65" onclick="return recordId('tid',65)">Jquery (174)</a><a title="Javascript" href="/tag/66" onclick="return recordId('tid',66)">Javascript (168)</a><a title="NoSQL" href="/tag/67" onclick="return recordId('tid',67)">NoSQL (6)</a><a title="CSS" href="/tag/68" onclick="return recordId('tid',68)">CSS (127)</a><a title="资料下载" href="/tag/69" onclick="return recordId('tid',69)">资料下载 (25)</a><a title="交易系统" href="/tag/70" onclick="return recordId('tid',70)">交易系统 (9)</a><a title="java工具类" href="/tag/71" onclick="return recordId('tid',71)">java工具类 (32)</a><a title="其它" href="/tag/72" onclick="return recordId('tid',72)">其它 (7)</a><a title="秕处理" href="/tag/73" onclick="return recordId('tid',73)">秕处理 (4)</a> </div> </div>  <div class="zj-no-wx-app widget widget_links"> <div class="title"> <h2 style="float: left;">友情链接</h2><h2 style="float: right;"><a class="zj-titles" href="/link">申请友链</a></h2> </div> <ul class="xoxo blogroll"> <li><a class="zj-titles" title="上海加盾信息科技有限公司" href="https://www.shanghaijiadun.com" target="_blank">上海加盾信息科技有限公司</a></li><li><a class="zj-titles" title="股票002162悦心健康资金分析" href="/stock/my" target="_blank">股票002162悦心健康资金分析</a></li><li><a class="zj-titles" title="张军博客" href="https://www.zhangjunbk.com/" target="_blank">张军博客</a></li><li><a class="zj-titles" title="张军博客-网址导航" href="https://www.zhangjunbk.com/web-nav/index.htm" target="_blank">张军博客-网址导航</a></li><li><a class="zj-titles" title="张军java工具类" href="http://www.zhangjunbk.com/otherlink/javatooldoc/" target="_blank">张军java工具类</a></li><li><a class="zj-titles" title="iBAAO壹宝头条" href="http://toutiao.ibaao.com" target="_blank">iBAAO壹宝头条</a></li><li><a class="zj-titles" title="快手号出售" href="https://www.weihaoyi.com" target="_blank">快手号出售</a></li><li><a class="zj-titles" title="张军博客-SpringBoot入门" href="https://zhangjunbk.com/Public/static/md/SpringBoot/index.html" target="_blank">张军博客-SpringBoot入门</a></li> </ul> </div>  <div class="zj-no-wx-app widget widget_links"> <div class="title"> <h2 style="float: left;">51链网站</h2> </div> <ul class="xoxo blogroll"> <li><a class="zj-titles" title="51链首页" href="https://www.51link.com?ruid=16279" target="_blank">51链首页</a></li> <li><a class="zj-titles" title="51链注册页" href="https://www.51link.com/mobileRegister?ruid=16279" target="_blank">51链注册页</a></li> <li><a class="zj-titles" title="广告出售页" href="https://www.51link.com/ad-sell?ruid=16279" target="_blank">广告出售页</a></li> <li><a class="zj-titles" title="友链出租页" href="https://www.51link.com/link-sell?ruid=16279" target="_blank">友链出租页</a></li> <li><a class="zj-titles" title="软文出售页" href="https://www.51link.com/article-sell?ruid=16279" target="_blank">软文出售页</a></li> <li><a class="zj-titles" title="友链交换页" href="https://www.51link.com/link-exchange?ruid=16279" target="_blank">友链交换页</a></li> </ul> </div>          </aside>  <script type="text/javascript"> $(function(){ }); </script> </section>   <footer class="footer"> <div class="footer-inner"> <div class="copyright pull-left"> <a href="/">军军小站|张军博客</a> 丨 <a target="_blank" href="https://www.shanghaijiadun.com/product#id-5">获取加密软件注册码</a>丨<a target="_blank" href="https://www.shanghaijiadun.com">上海加盾信息科技有限公司</a>丨<a href="/article/24">个人简介</a> 丨 © 2020-2030 版权所有丨<a target="_blank" href="https://beian.miit.gov.cn/">沪ICP备19026782号-2</a> | <a href="/link">申请友链</a> | 站长QQ：<a target="_blank" href="http://wpa.qq.com/msgrd?v=3&uin=360901061&site=qq&menu=yes">360901061</a> </div> </div> </footer> <div class="rollto zj-rollto"> <button class="btn btn-inverse zj-totop" data-type="totop" title="回顶部" zj-title-options="direction:'left'"> <i class="fa fa-arrow-up"></i> </button> <button class="btn btn-inverse zj-torespond" data-type="torespond" title="发评论" zj-title-options="direction:'left'"> <i class="fa fa-comment-o"></i> </button> </div> <div class="zj-mark"></div> <div class="zj-search-box zj-mini-search-box" style="position: fixed; top: 0px; background: #FFF; height: 100%; width: 100%; text-align: center; display: none; background: ; z-index: 2000"> <span class="close zj-close" style="top: 3%; right: 8%; font-size: 220%; color: #000;"></span> <form class="searchform themeform" role="form" action="/search" method="get" style="margin: 20% auto;"> <input style="font-size: 120%; margin-top: 10px;" type="ext" class="search" name="search_word" placeholder="搜索从这里开始..." value=""> <button class="btn btn-primary" type="button" style="margin-left: -4px;height: 36px !important;"> <span class="zj-icon-text">搜索</span> </button> </form> </div>  <script src="/Public/static/js/wxLogin.js?v=1.0.4"></script> <script src="/Public/static/js/jweixin-1.3.2.js?v=1.0.1"></script> <script src="/Template/default/Home/Public/js/zj.basic.js?v=1.0.4"></script> <script src="/Template/default/Home/Public/js/zj.jq.ui.js?v=1.0.4"></script> <script src="/Template/default/Home/Public/js/zj.jq.js?v=1.0.4"></script> <script src="/Template/default/Home/Public/js/zj.jq.web.js?v=1.0.5"></script> <script src="/Template/default/Home/Public/js/zj.validate.js?v=1.0.4"></script> <script src="/Template/default/Home/Public/js/qrcode.min.js?v=1.0.4"></script> <script src="/Public/static/ueditor1_4_3/third-party/SyntaxHighlighter/shCore.js?v=1.0.1"></script> <script src="/Public/static/js/stomp.js?v=1.0.1"></script> <script type="text/javascript"> $(document).ready(function(){ SyntaxHighlighter.all(); }); </script>  <script src="/Template/default/Home/Public/js/zj.app.js?v=1.0.4"></script> <script src="/Template/default/Home/Public/js/zj.login.reg.js?v=1.0.4"></script> <script type="text/javascript"> $(function() { $(".zj-rollto").returnTop($(".zj-totop")); if ($('.v-comment').length == 0) { $('.zj-torespond').remove(); } else { $('.zj-torespond').click(function() { $('.v-comment').focus(); }); } }); </script>    <script> (function(){ var src = "https://jspassport.ssl.qhimg.com/11.0.1.js?d182b3f28525f2db83acfaaf6e696dba"; document.write('<script src="' + src + '" id="sozz"><\/script>'); })(); </script> </body> </html>

热门排行

ActiveReports 报表控件官方中文入门教程 (1)-

vim——vim配置步骤

40种网页常用小技巧(javascript)

How To Install VMware Player In Ubuntu 12.04

20个HTML5视频播放器及代码

JavaScript 的性能优化：加载和执行