调用jQuery（借用官网的一句话：The Write Less, Do More）极大的简化了JavaScript编程
CSS 样式将表现与内容分离
话不多说，先上效果图：
代码如下：
<!DOCTYPE html> <html> <head> <title>The second html page</title> <style type="text/css"> ul li { list-style-type:georgian; text-align:left; } body { margin:10px; text-align:center; background-color:Orange; } header { height:80px; border:1px solid gray; width:99% } .left { border:1px solid gray; float:left; width:20%; height:520px; margin:0px; border-top-style:none; border-bottom-style:none; /*设置边框样式*/ } .main { width:79%; float:left; height:520px; /*border:1px solid gray;*/ border-right:1px solid gray; margin:0px; position:relative;/*设置成相对*/ } footer { clear:left; height:60px; border:1px solid gray; width:99% } #container { display:block; padding:5px; /* border:1px solid gray;*/ margin:5px; position:relative; } .small { display:block; border-bottom:1px solid gray;/*将缩略图，和大图隔开*/ } .small img { width:150px; height:120px; margin:5px; border:1px solid gray; padding:3px; } .mm { cursor:pointer; border-radius:5px;/*鼠标移入样式*/ } input[type="button"] { cursor:pointer; background-color:Orange; color:Lime; font-family:Arial; font-size:25px; height:50px; border:0px; width:50px; position:relative; top:150px; } #btnLeft { left:30px; float:left; } #btnRight { right:30px; float:right; } </style> <script type="text/javascript" src="https://www.jb51.net/js/jquery-3.1.1.min.js"></script> <script type="text/javascript"> $(document).ready(function () { //初始加载六张图片作为缩略图 for (var i = 0; i < 6; i++) { var src = "img/" + "0" + (i + 1).toString() + ".jpg"; var img = $("<img />").attr("id", (i + 1).toString()).attr("alt", (i + 1).toString()).attr("src", src); $("#small").append(img); } //设置缩略图的点击事件，以及鼠标移入，移出事件 $("#small img").click(function () { $("#img").css("display", "none"); var src = $(this).attr("src"); var alt = $(this).attr("alt"); var nAlt = parseInt(alt); $("#img").attr("alt", nAlt).attr("src", src).fadeIn(delay); }).mouseover(function () { $(this).addClass("mm"); }).mouseleave(function () { $(this).removeClass("mm"); }); var delay = 1000; //向左切换事件 $("#btnLeft").click(function () { $("#img").css("display", "none"); var alt = $("#img").attr("alt"); if (alt == "1") { alt = 7; } var nAlt = parseInt(alt) - 1; var src = "img/" + "0" + nAlt.toString() + ".jpg"; $("#img").attr("alt", nAlt).attr("src", src).fadeIn(delay); }); //向右切换事件 $("#btnRight").click(function () { $("#img").css("display", "none"); var alt = $("#img").attr("alt"); if (alt == "6") { alt = 0; } var nAlt = parseInt(alt) + 1; var src = "img/" + "0" + nAlt.toString() + ".jpg"; $("#img").attr("alt", nAlt).attr("src", src).fadeIn(delay); }); }); </script> </head> <body> <header> <h2>Html+jQuery + CSS 相册</h2> </header> <aside> <h3>相册说明</h3> <ul> <li><h4>准备阶段：</h4></li> <li>几张图片，最好大小一致，宽高比一致</li> <li>jQuery库文件</li> </ul> <ul> <li><h4>大致思路：</h4></li> <li>将界面分<b>上</b>，<b>中</b>（分 <b>左（20%）</b> <b>右（80%）</b>），<b>下</b> 几部分</li> <li>实现缩略图，依次放在一个容器中，并设置样式，时间</li> <li>实现左右切换的事件函数</li> </ul> </aside> <section> <div> </div> <div> <input type="button" value="<<" /> <img alt="1" src="https://www.jb51.net/img/01.jpg" /> <input type="button" value=">>" /> </div> </section> <footer> <div>This is the footer</div> </footer> </body> </html>