如何选择“A”类而不是“B”类的div？

I have some divs:

我有一些div：

<div class="A">"Target"</div>
<div class="A B">"NotMyTarget"</div>
<div class="A C">"NotMyTarget"</div>
<div class="A D">"NotMyTarget"</div>
<div class="A E">"NotMyTarget"</div>

Is there a CSS selector that will get me the div containing Target but not the divs containing NotMyTarget?

是否有一个CSS选择器，它将获取包含Target但不包含NotMyTarget的div的div？

Solution must work on IE7, IE8, Safari, Chrome, and Firefox

解决方案必须适用于IE7，IE8，Safari，Chrome和Firefox

Edit: So far Nick is the closest. It's clumsy and I don't like the solution, but at least it works:

编辑：到目前为止尼克是最接近的。它很笨拙，我不喜欢这个解决方案，但至少它有效：

.A
{
   /* style that all divs will take */
}
div.B 
{
  /* style that will override style .A */
}

3 个解决方案

#1

You can use the attribute selector to match the div that has only one class:

您可以使用属性选择器来匹配只有一个类的div：

div[class=A] {
  background: 1px solid #0f0;
}

If you want to select another div that has multiple classes, use quotes:

如果要选择具有多个类的另一个div，请使用引号：

div[class="A C"] {
  background: 1px solid #00f;
}

Some browsers do not support the attribute selector syntax. As usual, "some browsers" is a euphemism for IE 6 and older.

某些浏览器不支持属性选择器语法。像往常一样，“一些浏览器”是IE 6及更早版本的委婉说法。

另见：http：//www.quirksmode.org/css/selector_attribute.html

Full example:

完整示例：

<!DOCTYPE html>
<html>
<head>
  <style>
    .A { font-size:22px; }
    .B { font-weight: bold; border: 1px solid blue; }
    .C { color: green; }

    div[class="A"] {
      border: 1px solid red;
    }
    div[class="A B"] {
      border: 3px solid green;
    }
  </style>
</head>
<body>
  <div class="A">"Target"</div> 
  <div class="A B">"NotMyTarget"</div> 
  <div class="A C">"NotMyTarget"</div> 
  <div class="A D">"NotMyTarget"</div> 
  <div class="A E">"NotMyTarget"</div> 
</body>
</html>

EDIT 2014-02-21: Four years later, :not is now widely available, though verbose in this specific case:

编辑2014-02-21：四年后，：现在没有广泛使用，虽然在这个特定情况下冗长：

.A:not(.B):not(.C):not(.D):not(.E) {
  border: 1px solid red;
}

Unfortunately, this doesn't work in IE 7–8 as specified in the question: http://caniuse.com/#search=:not

不幸的是，这在问题中指定的IE 7-8中不起作用：http：//caniuse.com/#search=：not

#2

.A:not(.B) {}

But guess who doesn't support that... Indeed, IE<=8.

但猜猜谁不支持......确实，IE <= 8。

#3

I think the best you can do (until CSS 3) is override the styles in this case with what you don't want from class A B in A, like this:

我认为你能做到的最好（直到CSS 3）在这种情况下用你不想要的A A中的A类来覆盖样式，如下所示：

.A.B { /* Styles */ }
.A { /* Reverse any styling you don't want */ }

#1