一:css3属性选择器:
img[alt]{ border:2px dashed #000;}
这个选择器会匹配页面标签中任何一个含有alt属性的图片标签。
还可以通过设定属性值来缩小匹配范围:如下代码:
img[alt="atwi_oscar"]{ border:2px dashed #000;}
css3的子字符串匹配属性选择器
(1)‘匹配开头’的属性选择器依法如下:
Element[attribute^="value"],实例代码如下:
img[alt^="filem"]{ border:2px dashed #000; }
(2)'匹配包含内容'的属性选择器
Element[attribute*="value"],实例代码如下:
img[alt*="filem"]{ border:2px dashed #000;}
(3)'匹配结尾'的属性选择器
Element[attribute$="value"],实例代码如下:
img[alt$="filem"]{ border:2px dashed #000;}
二:(:not)选择器:
否定伪类选择器,用于选择不满足某些条件的元素,例如:
nav ul li:not(.internal) a{color:#000;}
多提一点关于伪元素的:
对伪元素的修正
P:first-line 会选中
标签的第一行内容,
P:first-letter会选中其中第一个字母。
css3要求对伪元素使用2个冒号以便对伪类进行区别。但IE8及更低的版本无法识别2个冒号的语法,它们只识别一个冒号。
如果您觉得本文对您的学习有所帮助,请多支持与鼓励。

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