JQuery ul li 选择列表

Question

尝试使用 JQuery 使用类 next 和类 prev 滚动浏览 ul li 列表，例如

<ul class="selectoption">
    <li> Item 1</li>
    <li> Item 2</li>
    <li> Item 3</li>
    <li> ...   </li>
</ul>
<a href="" class="next">Next</a>
<a href="" class="prev">Back</a>

唯一的事情是我只希望所选的 li 可见。那么需要以某种方式索引 li 吗？非常感谢您的帮助 - 提前致谢

Answer 1

这应该可以做到:

// Hide all but the first
$('.selectoption li').not(':first').hide();

// Handle the click of prev and next links
$('.prev, .next').click(function() {
    // Determine the direction, -1 is prev, 1 is next
    var dir = $(this).hasClass('prev') ? -1 : 1;
    // Get the li that is currently visible
    var current = $('.selectoption li:visible');

    // Get the element that should be shown next according to direction
    var new_el = dir < 0 ? current.prev('li') : current.next('li');

    // If we've reached the end, select first/last depending on direction
    if(new_el.size() == 0) {
        new_el = $('.selectoption li:'+(dir < 0 ? 'last' : 'first'));
    }

    // Hide them all..
    $('.selectoption li').hide();
    // And show the new one
    new_el.show();

    // Prevent the link from actually redirecting the browser somewhere
    return false;
});