CSS :: before :: after伪元素动态宽度

Question

我想用单个div元素和css伪元素（例如::before制作rate stars进度条。

我唯一不能做的是使用Javascript操作::before元素的宽度。

这是我的例子：

 .review-rate { background-image: url(data:image/png;base64,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); background-repeat: repeat-x; width: 100px; height: 18px; } .review-rate::before { content: ""; display: block; width: attr(data-width); height: 18px; width: 55%; background-image: url(data:image/png;base64,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); background-repeat: repeat-x; background-position: 0 -18px; } 

 <div class="review-rate" data-toggle="review" data-value="3.5" data-width="50" data-count="17"></div> 

有没有办法操纵::before元素的width ？

也许像width: attr(data-width); ？

任何帮助将不胜感激。

Answer 1

我知道改变的一种方式:before ＆ :after CSS动态是一个@Brett代物所提到的，添加的风格标签。

在您的情况下，您只需切换角色:before ＆ div 。 然后使用div宽度而不是:before 。 像这样：

 .review-rate { background-image: url("data:image/png;base64,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"); background-position: 0 -18px; background-repeat: repeat-x; height: 18px; overflow: visible; position: relative; width: 50px; } .review-rate::before { background-image: url("data:image/png;base64,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"); background-repeat: repeat-x; content: ""; display: block; height: 18px; position: relative; width: 100px; z-index: -1; } 

  <div class="review-rate" data-toggle="review" data-value="3.5" data-width="50" data-count="17"></div> 

Answer 2

虽然它不理想，但您可以使用带有新width值的jQuery将新的<style>元素附加到页面。

$('head').append('<style>.review-rate:before{width:75%}</style>');

这是一个演示 。

更新
正如Imran在下面的评论中所指出的，随着时间的推移，上述方法会产生许多<style>标签。 为了防止这种情况，可以使用append和replaceWith的组合来append <style>标记的数量保持为最小。

if ($('head style[data-class="review-rate"]').length) {
    $('head style[data-class="review-rate"]').replaceWith('<style data-class="review-rate">.review-rate:before{width:75%}</style>')       
} else {
    $('head').append('<style data-class="review-rate">.review-rate:before{width:35%}</style>');
}