为什么这个CSS：not（）声明过滤掉？ [英] Why doesn't this CSS :not() declaration filter down?

问题描述

我想选择不是特定类的后代的跨度，我们称之为no。这是我的CSS：

I want to select spans that are not the descendants of a specific class, let's call it "no". Here's my CSS:

div:not(.no) span{background-color:#00f;}

这是HTML

<div>
    <span>yes 1</span>
</div>
<div class="no">
        <span>no 1</span>
</div>
<div class="no">
    <div>
           <span>no 2</span>
    </div>
</div>

两个问题：

1. 为什么我的CSS适用于yes 1和no 2？



2. 如果切换到通用选择器，为什么整个事件会中断？

1. Why does my CSS apply to both yes 1 and no 2?

2. Why does the whole thing break if I switch to a universal selector?

*:not(.no) span{background-color:#00f;}

以下是JSFiddle中的代码： http://jsfiddle.net/stephaniehobson/JtNZm/

Here's the code in JSFiddle: http://jsfiddle.net/stephaniehobson/JtNZm/

推荐答案

1. span 元素父元素 div 元素没有类没有，不管是否有任何其他祖先有它：

1. Both of the span elements' parent div elements don't have the class no, regardless of whether any other ancestors do have it or not:

<div> <!-- This is div:not(.no), pretty much a given -->
    <span>yes 1</span>
</div>

<div class="no"> <!-- In this case, although this is div.no... -->
    <div>        <!-- ... this is div:not(.no)! -->
           <span>no 2</span>
    </div>
</div>

html c $ c> body ，它们是您的 div 和 span 元素的祖先，满足 *：not（.no）当使用通用选择器（或更确切地说，省略类型选择器时）。这会使 span 元素的全部具有背景颜色。

Both html and body, which are ancestors of your div and span elements, satisfy *:not(.no) when using a universal selector (or rather, when omitting a type selector). This causes all of your span elements to have the background color.

一个解决方法是使用子组合器将您的否定过滤器锚定到 body 元素，如果您的顶级 div 元素将始终是 body 的子元素：

One solution to this is to anchor your negation filter to the body element using the child combinator, if your top-level div elements will always be children of body:

body > div:not(.no) span { background-color: #00f; }

jsFiddle demo

另一个解决方案是简单地使用重写样式。

Another solution is to simply use override styles.

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