jQuery实现轮播图/index.html

<!DOCTYPE html>
<html lang="zh-cn">
<head>
    <meta charset="utf-8">
    <title>jQuery实现轮播图</title>
    <!-- 优先使用 IE 最新版本和 Chrome -->
    <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />
    
    <!-- 开启响应式 -->
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <style>
        body {
            padding: 0;
            margin: 0;
        }

        ul,
        li {
            padding: 0;
            margin: 0;
            list-style: none;
        }
        .clearfix:after {
            content: '';
            display: block;
            clear: both;
        }

        .carousel {
            position: relative;
            width: 1000px;
            height: 575px;
            margin: 20px auto;
            overflow: hidden;
        }
        .carousel a {
            display: block;
        }
        .carousel .btn {
            position: absolute;
            top: 50%;
            transform: translateY(-50%);
        }
        .carousel .btn.prev {

        }
        .carousel .btn.next {
            right: 0;
        }


        .slides-img {
            position: absolute;
            display: block;
            width: 4000px;
            height: 575px;
        }

        .slides-img > li {
            float: left;
        }

        .slides-img img {
            width: 1000px;
            height: 575px;
        }

        .shulling-btn {
            position: absolute;
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
        }
        .shulling-btn > li {
            float: left;
            margin: 20px 20px;
            width: 50px;
            height: 10px;
            background: #fff;
            border: 2px solid #fff;
            cursor: pointer;
            border-radius: 6px;
            box-shadow: 2px 2px 3px #333;
        }
        .shulling-btn .active {
            background: #333;
        }
    </style>
</head>
<body>
    <div class="carousel clearfix">
        <ul class="slides-img">
            <li data-index="0"><a href="#"><img src="images/1.jpg" alt=""></a></li>
            <li data-index="1"><a href="#"><img src="images/2.jpg" alt=""></a></li>
            <li data-index="2"><a href="#"><img src="images/3.jpg" alt=""></a></li>
            <li data-index="3"><a href="#"><img src="images/4.jpg" alt=""></a></li>
        </ul>
        <a href="#" class="btn prev"><img src="images/prev.png" alt=""></a>
        <a href="#" class="btn next"><img src="images/next.png" alt=""></a>
        <ul class="shulling-btn">
            <li class="active"></li>
            <li></li>
            <li></li>
            <li></li>
        </ul>
    </div>
    <script src="https://cdn.bootcss.com/jquery/2.0.0/jquery.min.js"></script>
    <script>
        ///////自定义变量/////////
        var $carouselBox = $('.carousel'),
            $slidesUl = $('.slides-img'),               
            $slidesLi = $('.slides-img > li'),
            $prev = $('.btn.prev'),
            $next = $('.btn.next'),
            $shullingBtn = $('.shulling-btn > li');

        var $firstLi = $slidesLi.first(),
            $lastLi = $slidesLi.last(),
            $slidesNum = $slidesLi.length;
            $slidesWidth = $firstLi.width();
            $index = 0;

        $slidesUl.append($firstLi.clone());      // 添加克隆元素
        $slidesUl.prepend($lastLi.clone());      // 添加克隆元素
        $slidesUl.css({                        
                        width: $slidesUl.children().length * $slidesWidth + 'px',
                        left: -$slidesWidth
                     });
        ///////绑定事件/////////
        $carouselBox.on('mouseenter', stopTime);    // 鼠标移动到图片上轮播停止
        $carouselBox.on('mouseleave', auto);        // 鼠标移开后开始轮播

        $prev.on('click', function(e) {
            e.preventDefault();
            prev();
        });

        $next.on('click', function(e) {
            e.preventDefault();
            next();
        });

        $shullingBtn.on('click', function (){
            $BtnIndex = $(this).index();
            if($index === $BtnIndex) return;
            console.log($BtnIndex),
            console.log($index);
            ($index > $BtnIndex) ? prev($index-$BtnIndex) : next($BtnIndex-$index);
        });


        var lock = true;           //  状态锁防止连续点击重复执行函数

        ///////处理函数/////////
        function prev(n=1) {
            if(!lock) return;
            lock = false;
            $slidesUl.animate({ 'left': '+='+ $slidesWidth*n +'px' }, function() {
                $index -= n;
                if($index < 0) {
                $('.slides-img').css({ 'left': -($slidesWidth*$slidesNum) });
                $index = $slidesNum -1;
                
            }
            lock = true;
            gotoBtn();
            });
            
        }

        function next(n=1) {
            if(!lock) return;
            lock = false;
            $slidesUl.animate({ 'left': '-='+ $slidesWidth*n +'px' }, function() {
                $index += n;
                if($index === $slidesNum) {
                $('.slides-img').css({ 'left': -$slidesWidth });
                $index = 0;
                
            }
            lock = true;
            gotoBtn();
            });
            
        }

        function gotoBtn() {
            $shullingBtn.removeClass('active')
            .eq($index)
            .addClass('active');
        }
        
        // 自动轮播
        function auto() {
            check = setInterval(next, 3500);
            
        }
        // 停止自动轮播
        function stopTime() {
            clearInterval(check);
        }
        auto();
    </script>
</body>
</html>