javascript - 显示随机类

Question

假设我有一些类:

<div class="something" style="display: none">Some text I would like to show</div>
<div class="something" style="display: none">Some text2 I would like to show</div>
<div class="something" style="display: none">Some text3 I would like to show</div>
<div class="something" style="display: none">Some text4 I would like to show</div>
<div class="something" style="display: none">Some text5 I would like to show</div>

而且我想每隔几秒显示一次随机类。我想伪代码应该是这样的:

    setInterval(function() {
        $('.something').hide();
        var rand_number = random(1, ('.something').length);
        $('.something').array[rand_number].show();
    }, 5000);

谢谢。

Answer 1

尽量避免过于频繁地评估 $('.something'):

setInterval(function() {
    var $s = $('.something');
    var r = Math.floor(Math.random() * $s.length);
    $s.hide().eq(r).show();
}, 5000);

如果您知道元素列表在文档加载后不会改变，您可以进一步简化:

$(function() { // short-hand for document.ready
    var $s = $('.something');
    var count = $s.length;
    setInterval(function() {
        var r = Math.floor(Math.random() * count);
        $s.hide().eq(r).show();
    }, 5000);
});