将jquery和公共样式缓存到localStorage，可以减少Http请求，从而优化页面加载时间，下面的代码可以实现此功能：

<script type="text/javascript"> //入口函数 if (window.localStorage) { initJs(); initCss("css", "/gfdzp201508257998/Turntable/Style/css_whir.css"); } else { addFile("/gfdzp201508257998/Turntable/Script/jquery-1.8.3.min.js", "js"); addFile("/gfdzp201508257998/Turntable/Script/whir.turntable.js", "js"); addFile("/gfdzp201508257998/Turntable/Style/css_whir.css", "css"); } //第一步：加载页面js：先加载jQuery后加载用户脚本 function initJs() { var name = "jquery"; var url = "/gfdzp201508257998/Turntable/Script/jquery-1.8.3.min.js"; var xhr; var js = window.localStorage ? localStorage.getItem(name) : ""; if (js == null || js.length == 0) { if (window.ActiveXObject) { xhr = new ActiveXObject("Microsoft.XMLHTTP"); } else if (window.XMLHttpRequest) { xhr = new XMLHttpRequest(); } xhr.open("GET", url); xhr.send(null); xhr.onreadystatechange = function () { if (xhr.readyState == 4 && xhr.status == 200) { js = xhr.responseText; localStorage.setItem(name, js); js = js == null " : js; addTxt(js, "js"); initTurntable(); //确保先引用Jquery } }; } else { addTxt(js, "js"); initTurntable(); } } //加载自定义脚本 function initTurntable() { var name = "turntable"; var url = "/gfdzp201508257998/Turntable/Script/whir.turntable.js"; var xhr; var js = window.localStorage ? localStorage.getItem(name) : ""; if (js == null || js.length == 0) { if (window.ActiveXObject) { xhr = new ActiveXObject("Microsoft.XMLHTTP"); } else if (window.XMLHttpRequest) { xhr = new XMLHttpRequest(); } xhr.open("GET", url); xhr.send(null); xhr.onreadystatechange = function () { if (xhr.readyState == 4 && xhr.status == 200) { js = xhr.responseText; localStorage.setItem(name, js); js = js == null " : js; addTxt(js, "js"); } }; } else { addTxt(js, "js"); } } //第二步：初始化Css function initCss(name, url) { var xhr; var css = window.localStorage ? localStorage.getItem(name) : ""; if (css == null || css.length == 0) { if (window.ActiveXObject) { xhr = new ActiveXObject("Microsoft.XMLHTTP"); } else if (window.XMLHttpRequest) { xhr = new XMLHttpRequest(); } xhr.open("GET", url); xhr.send(null); xhr.onreadystatechange = function () { if (xhr.readyState == 4 && xhr.status == 200) { css = xhr.responseText; localStorage.setItem(name, css); css = css == null " : css; css = css.replace(/images//g, "style/images/"); addTxt(css, "css"); } }; } else { css = css.replace(/images//g, "style/images/"); addTxt(css, "css"); } } //辅助方法1：动态添加js，css文件引用 function addFile(url, fileType) { var head = document.getElementsByTagName('HEAD').item(0); var link; if (fileType == "js") { link = document.createElement("script"); link.type = "text/javascript"; link.src = url; } else { link = document.createElement("link"); link.type = "text/css"; link.rel = "stylesheet"; link.rev = "stylesheet"; link.media = "screen"; link.href = url; } head.appendChild(link); } //辅助方法2：动态添加js，css文件内容 function addTxt(text, fileType) { var head = document.getElementsByTagName('HEAD').item(0); var link; if (fileType == "js") { link = document.createElement("script"); link.type = "text/javascript"; link.innerHTML = text; } else { link = document.createElement("style"); link.type = "text/css"; link.innerHTML = text; } head.appendChild(link); } </script>

查看写入记录：

封装成JS插件：

/** * 插件功能：使用localStorage缓存js和css文件，减少http请求和页面渲染时间，适用于Web移动端H5页面制作。 * 插件作者：zhangqs008@163.com * 使用方法： * 1.使用此插件前，需要给插件的pageVersion变量赋值，建议变量值由服务器后端输出，当需要更新客户端资源时，修改版本值即可。 * 2.加载Js：由于js加载有顺序要求，所以需要将后加载的脚本作为前一个脚本的回调参数传入，如： * whir.res.loadJs("jquery", "<%= BasePath %>Turntable/Script/jquery-1.8.3.min.js", * function () { * whir.res.loadJs("turntable", "Script/whir.turntable.js", null); * }); * 3.加载css，如：whir.res.loadCss("css", "/Style/css_whir.css", null); */ var whir = window.whir || {}; whir.res = { pageVersion: "", //页面版本，由页面输出，用于刷新localStorage缓存 //动态加载js文件并缓存 loadJs: function (name, url, callback) { if (window.localStorage) { var xhr; var js = localStorage.getItem(name); if (js == null || js.length == 0 || this.pageVersion != localStorage.getItem("version")) { if (window.ActiveXObject) { xhr = new ActiveXObject("Microsoft.XMLHTTP"); } else if (window.XMLHttpRequest) { xhr = new XMLHttpRequest(); } if (xhr != null) { xhr.open("GET", url); xhr.send(null); xhr.onreadystatechange = function () { if (xhr.readyState == 4 && xhr.status == 200) { js = xhr.responseText; localStorage.setItem(name, js); localStorage.setItem("version", whir.res.pageVersion); js = js == null " : js; whir.res.writeJs(js); if (callback != null) { callback(); //回调，执行下一个引用 } } }; } } else { whir.res.writeJs(js); if (callback != null) { callback(); //回调，执行下一个引用 } } } else { whir.res.linkJs(url); } }, loadCss: function (name, url) { if (window.localStorage) { var xhr; var css = localStorage.getItem(name); if (css == null || css.length == 0 || this.pageVersion != localStorage.getItem("version")) { if (window.ActiveXObject) { xhr = new ActiveXObject("Microsoft.XMLHTTP"); } else if (window.XMLHttpRequest) { xhr = new XMLHttpRequest(); } if (xhr != null) { xhr.open("GET", url); xhr.send(null); xhr.onreadystatechange = function () { if (xhr.readyState == 4 && xhr.status == 200) { css = xhr.responseText; localStorage.setItem(name, css); localStorage.setItem("version", whir.res.pageVersion); css = css == null " : css; css = css.replace(/images//g, "style/images/"); //css里的图片路径需单独处理 whir.res.writeCss(css); } }; } } else { css = css.replace(/images//g, "style/images/"); //css里的图片路径需单独处理 whir.res.writeCss(css); } } else { whir.res.linkCss(url); } }, //往页面写入js脚本 writeJs: function (text) { var head = document.getElementsByTagName('HEAD').item(0); var link = document.createElement("script"); link.type = "text/javascript"; link.innerHTML = text; head.appendChild(link); }, //往页面写入css样式 writeCss: function (text) { var head = document.getElementsByTagName('HEAD').item(0); var link = document.createElement("style"); link.type = "text/css"; link.innerHTML = text; head.appendChild(link); }, //往页面引入js脚本 linkJs: function (url) { var head = document.getElementsByTagName('HEAD').item(0); var link = document.createElement("script"); link.type = "text/javascript"; link.src = url; head.appendChild(link); }, //往页面引入css样式 linkCss: function (url) { var head = document.getElementsByTagName('HEAD').item(0); var link = document.createElement("link"); link.type = "text/css"; link.rel = "stylesheet"; link.rev = "stylesheet"; link.media = "screen"; link.href = url; head.appendChild(link); } }

调用该插件：

<script type="text/javascript"> //入口函数 whir.res.pageVersion = "1002"; //页面版本，用于检测是否需要更新缓存 whir.res.loadJs("jquery", "/gfdzp201508257998/Turntable/Script/jquery-1.8.3.min.js", function () { whir.res.loadJs("turntable", "/gfdzp201508257998/Turntable/Script/whir.turntable.js", null); }); whir.res.loadCss("css", "/gfdzp201508257998/Turntable/Style/css_whir.css", null); </script>

以上所述是小编给大家介绍的移动端使用localStorage缓存Js和css文的方法(web开发)，希望对大家有所帮助，如果大家有任何疑问请给我们留言，小编会及时回复大家的。在此也非常感谢大家对查字典教程网的支持！