定时器js

<div class="lycon">
    <div class="wh">
        <div class="xw_tt" style="color:#ffffff">应用领域</div>
        <div class="xw_tt2" style="color:#c0bebe">高质服务+合法合规的安全手续，让您的废炭处理无后顾之忧。</div>

        <div class="flex_a2">
            <div class="ys_ll ys_ll-a ys-ll2" {{ app( 'visual').url( 'section', 77263) }}>
                {% for value in app('section').id('77263') %}
                <li>
                    <a href="{{ value.url }} " class="clearfix">
                        <div class="img_aq">
                            <img src="{{ value.img[0] }}" alt="{{ value.name }}">
                        </div>
                        <div class="nnrr">
                            <h3>{{ value.name }}</h3>
                            <h4>{{ value.fname }}</h4>
                        </div>
                    </a>
                </li>
                {% endfor %}
            </div>

            <div class="ys_ll visible-xs visible-sm" {{ app( 'visual').url( 'section', 59079) }}>
                {% for value in app('section').id('59079') %}
                <li>
                    <a href="{{ value.url }} " class="clearfix">
                        <div class="img_aq">
                            <img src="{{ value.img[0] }}" alt="{{ value.name }}">
                        </div>
                        <div class="nnrr">
                            <h3>{{ value.name }}</h3>
                            <h4>{{ value.fname }}</h4>
                        </div>
                    </a>
                </li>
                {% endfor %}
            </div>


            <div class="yuan_a">
                {% for value in app('section').id('59079') %}
                <ul class="p_p1 ppa">
                    <img src="{{ value.img[1] }}" alt="{{ value.name }}">
                </ul>
                {% endfor %} {% for value in app('section').id('77263') %}
                <ul class="p_p2 ppa">
                    <img src="{{ value.img[1] }}" alt="{{ value.name }}">
                </ul>
                {% endfor %}
            </div>

            <div class="ys_ll ys_ll2 ys_ll-b ys-ll2 hidden-sm hidden-xs" {{ app( 'visual').url( 'section', 59079) }}>
                {% for value in app('section').id('59079') %}
                <li>
                    <a href="{{ value.url }} " class="clearfix">
                        <div class="img_aq fr">
                            <img src="{{ value.img[0] }}" alt="{{ value.name }}">
                        </div>

                        <div class="nnrr ">
                            <h3>{{ value.name }}</h3>
                            <h4>{{ value.fname }}</h4>
                        </div>
                    </a>
                </li>
                {% endfor %}
            </div>
           
        </div>
    </div>
</div>



<script type="text/javascript">
    $(document).ready(function() {
        /* 初始化：选择 .ys_ll-a 和 .ys_ll-b 下的所有 <li> 元素 */
        var combinedItemsA = $(".ys_ll-a li"); // 选择 .ys_ll-a 里的 li 元素
        var combinedItemsB = $(".ys_ll-b li"); // 选择 .ys_ll-b 里的 li 元素
        var combinedContent = $(".yuan_a .ppa"); // 选择 .yuan_a 下的 .ppa 元素
        var currentIndex = 0; // 当前索引，用于跟踪当前激活的项目

        // 设置初始激活状态：第一个 <li> 和第一个 .ppa 元素
        combinedItemsA.eq(0).addClass('active');
        combinedContent.eq(0).addClass('active');

        /* 悬停效果 - .ys_ll-a */
        combinedItemsA.hover(function() {
            var _id = $(this).index(); // 获取当前悬停项目的索引
            combinedItemsA.eq(_id).addClass('active').siblings().removeClass('active'); // 激活当前的 .ys_ll-a li
            combinedItemsB.removeClass('active'); // 移除 .ys_ll-b 中的 active 类
            combinedContent.eq(_id).addClass('active').siblings().removeClass('active'); // 同步切换 .ppa 中的内容
            clearInterval(autoSwitch); // 悬停时，清除定时器，停止自动切换
        }, function() {
            autoSwitch = setInterval(switchTab, 3000); // 悬停结束后，重新启动自动切换
        });

        /* 悬停效果 - .ys_ll-b */
        combinedItemsB.hover(function() {
            var _id = $(this).index(); // 获取当前悬停项目的索引
            combinedItemsB.eq(_id).addClass('active').siblings().removeClass('active'); // 激活当前的 .ys_ll-b li
            combinedItemsA.removeClass('active'); // 移除 .ys_ll-a 中的 active 类
           
            // 切换到 .yuan_a 中对应的 .ppa 项
            var targetIndex = _id + 2; // 对应的 .ppa 项索引，第一个 li 切换到第 3 个，第二个切换到第 4 个
            combinedContent.eq(targetIndex).addClass('active').siblings().removeClass('active'); // 激活对应的 .ppa 项
            clearInterval(autoSwitch); // 悬停时，清除定时器，停止自动切换
        }, function() {
            autoSwitch = setInterval(switchTab, 3000); // 悬停结束后，重新启动自动切换
        });

        /* 自动切换功能，定时器 */
        function switchTab() {
            currentIndex = (currentIndex + 1) % (combinedItemsA.length + combinedItemsB.length); // 计算下一个索引，合并 .ys_ll-a 和 .ys_ll-b
            if (currentIndex < combinedItemsA.length) {
                combinedItemsA.eq(currentIndex).addClass('active').siblings().removeClass('active'); // 切换到 .ys_ll-a 的下一个 <li>
                combinedItemsB.removeClass('active'); // 移除 .ys_ll-b 的 active 类
                combinedContent.eq(currentIndex).addClass('active').siblings().removeClass('active'); // 切换对应的 .ppa 内容
            } else {
                var newIndex = currentIndex - combinedItemsA.length; // 计算在 .ys_ll-b 中的索引
                combinedItemsB.eq(newIndex).addClass('active').siblings().removeClass('active'); // 切换到 .ys_ll-b 的下一个 <li>
                combinedItemsA.removeClass('active'); // 移除 .ys_ll-a 的 active 类
               
                // 切换到 .yuan_a 中对应的 .ppa 项
                var targetIndex = newIndex + 2; // 对应的 .ppa 项索引
                combinedContent.eq(targetIndex).addClass('active').siblings().removeClass('active'); // 激活对应的 .ppa 项
            }
        }

        var autoSwitch = setInterval(switchTab, 3000); // 每 3 秒自动切换一次
    });

</script>