jQuery实现Tab栏特效
小白可别不举铁 人气:0一、jQuery排序
eq（）排序，可以看作是一个筛选方法
- jQuery 中获得的对象，内部包含选择的一组原生 js 对象，在 jQuery 对象中会进行一个新的大的排序，这个排序与原来的 HTML 结构没有关系。
所以eq() 方法在 jQuery 对象中通过下标获取某个对象，下标是 jQuery 对象中的大的排序的下标。
//选中所有p标签
var $ps = $("p");
//生成了一个jquery对象，内部包含了所有的元素js对象
// 是一个类数组对象，内部会按照获取顺序进行一个大排序
// 排序与自己原来的父级没有关系，只与在jQuery对象中的新的位置有关
// 给指定位置对象添加颜色
$ps.eq(1).css("background-color","pink")
$ps.eq(4).css("background-color","skyblue")
$ps.eq(8).css("background-color","purple")
$ps.eq(7).css("background-color","lightgreen")
$ps.eq(10).css("background-color","orange")
//对所有获取的元素进行了排序，跟原来的结构没有关系
第三组div里p标签
<div class="b3">
<p></p>
<p class="b2p"></p>
<p></p>
<p></p>
<p></p>
</div>
----------
<script>
// 通过类名选中标签
$(".b2p").eq(2).css("background-color","red")
//得到第3组类名为b2p的 p 标签，让它变成红色
</script>
二、index（）方法
- jQuery 对象调用
index()方法时，得到的是它自己在 HTML 结构中的兄弟中的下标位置。与新生成的jQuery 对象内部的大排序没有关系。 - 它依赖于自身元素在父级中同级元素之间的位置
//index（） 兄弟中的排序
$ps.click(function(){
//点击输出自己的index值
console.log($(this).index());
})
上图为依次点击图中p标签后，所显示结果
jQuery中设置排他方法，在jQuery中可以通过this特殊设置进行链式调用，让兄弟通过siblings方法，批量设置成默认效果。
三、应用：Tab栏特效中的排他
- 自己的级别的排他：给自己this添加（要添加的属性）类名，让其他的兄弟删除该类名。
- 对应的部分的排他：给对应位置的元素添加 （要添加的属性）类名，其他兄弟删除该类名。
- 找对应关系，使用的是自己的index（）下标，让另一组中下标相同的项作为对应项。
- 通过选中另一组的对应项利用eq（）方法选择下标项。
html部分：
<style>
*{
margin: 0;
padding: 0;
}
ul{
list-style: none;
}
.tab{
width: 360px;
height: 200px;
border-top: 2px solid #206f96;
margin: 100px;
float: left;
}
.tab .title{
width: 360px;
height: 40px;
overflow: hidden;
}
.tab .title span{
float: left;
width: 88px;
height: 38px;
border: 1px solid #52819c;
border-bottom: 1px solid #52819c;
background-color: #c0f3f7;
font: 16px/34px "SunSim";
text-align: center;
}
.tab .title span.current{
height: 40px;
background-color: rgb(255, 255, 255);
}
.tab .title span a{
color: rgb(34, 34, 34);
text-decoration: none;
}
.tab .detail{
height: 258px;
padding: 17px 0 0 9px;
}
.tab .detail ul{
display: none;
}
.tab .detail ul.current{
display: block;
}
.tab .detail ul li a{
color: #000;
text-decoration: none;
}
.tab .detail ul li.first{
font-weight: bold;
}
</style>
</head>
<body>
<div class="tab">
<div class="title">
<span class="current"><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >上路</a></span>
<span><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >中路</a> / <a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >辅助</a></span>
<span><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >打野</a></span>
<span><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >下路</a></span>
</div>
<div class="detail">
<ul class="current">
<li class="first"><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >夏侯惇</a></li>
<li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >李信</a></li>
<li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >曜</a></li>
<li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >吕布</a></li>
</ul>
<ul>
<li class="first"><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >上官婉儿</a></li>
<li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >弈星</a></li>
<li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >甄姬</a></li>
<li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >女娲</a></li>
</ul>
<ul>
<li class="first"><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >赵云</a></li>
<li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >露娜</a></li>
<li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >娜可露露</a></li>
<li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >夏侯惇</a></li>
</ul>
<ul>
<li class="first"><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >后羿</a></li>
<li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >虞姬</a></li>
<li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >狄仁杰</a></li>
<li><a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >鲁班</a></li>
</ul>
</div>
</div>
</body>script部分:
<script src="../jq/jquery-1.12.4.min.js"></script>
<script>
//获取元素
var $spans = $(".tab .title span");
//添加鼠标移上事件
$spans.mouseenter(function(){
// 存储对应span下标的下标值，后面需要找到对应的ul
var ind = $(this).index();
// 自己级别的排他
//$(this).addClass("current").siblings().removeClass("current");
$(".tab .detail ul").eq(ind)
.addClass("current").siblings().removeClass("current")
</script>上面的方法在一个tab栏中效果实现没有问题， 但是当页面有多个tab栏时，jQuery对象中大排序和index获取的顺序就会不统
出现问题
解决方法：span和ul的查找全部使用链式调用，通过节点关系查找
<script src="../jq/jquery-1.12.4.min.js"></script>
<script>
// 查找所有对应ul时，不要单独选择所有的ul，通过当前的 this 的节点关系查找
// 链式调用的方式，找到自己父级中的兄弟中的所有子级
$(this).addClass("current").siblings().removeClass("current")
.parent().siblings().children().eq(ind).addClass("current")
.siblings().removeClass("current");
// title的兄弟detail
})
</script>
jQuery 对象进行的操作都是批量操作，批量操作只能执行一些简单的效果，如果想对 JQ 对象中的每一个元素以及内部的后
代元素进行一些复杂操作，程序很难执行
each（）遍历
each（）的参数是一个函数
作用：对jQuery对象中的元素每一个都执行函数内部的操作
each方法基本原理就是for循环，从对象的下标为0的项一直遍历到最后一项，然后对每一项进行操作
优点：
each的函数内部也有一个this，指向的是进来遍历的每一次的元素。
<body>
<div class="box">
<p></p>
<p></p>
<p></p>
<p></p>
<h2>h2</h2>
</div>
<div class="box">
<p></p>
<p></p>
<p></p>
<p></p>
<h2>h2</h2>
</div>
</body>
<script src="../jq/jquery-1.12.4.min.js"></script>
<script>
var $box = $(".box");
//每个div内的第二个p添加红色
$box.each(function(){
$(this).children().eq(1).css("background-color","pink");
})
</script>each的函数可以传一个参数i，i表示的是这一次的遍历对象在整体的jQuery对象大排序中的下标位置
//通过each()操作
$ps.each(function(i){
// i 记录的是这一次遍历时，当前元素在jQuery对象大排序中的位置
$(this).click(function(){
console.log($(this).index())
//这个内部的this是事件源
console.log(i);
})
})
同理，如果想实现表格隔列变色的话，依靠jQuery大排列顺序来实现奇偶不同变色的话，后期若给表格再添加列，都会出现问题，无法对应。所以使用each（）方法，将每一行作为一个操作单元，让每一行中的列进行隔列变色
var $trs = $("tr");
$trs.each(function(){
$(this).children(":odd").css("background-color","skyblue");
})另一种方法就是使用td判断，只要不使用jQuery的大排序，就不会影响后期插入列
$("td").each(function(){
//判断当前td在父级中所处的位置
if($(this).index() % 2 == 0){
$(this).css("background-color","skyblue");
}
})加载全部内容