CSS3选择器

CSS3选择器原说明文档：http://www.w3.org/TR/css3-selectors/
翻 译如下，仅供参考：

*下面格式没有绘制表格，使用百度文章编辑器的三格布局，请谅解

形式 ----------------------- * E E[foo] E[foo="bar"] E[foo~="bar"] E[foo^="bar"] E[foo$="bar"] E[foo*="bar"] E[foo|="en"] E:root E:nth-child(n) E:nth-last-child(n) E:nth-of-type(n) E:nth-last-of-type(n) E:first-child E:last-child E:first-of-type E:last-of-type E:only-child E:only-of-type E:empty E:link E:vidited E:active E:hover E:focus E:target E:lang(fr) E:enabled E:disabled E:checked E::first-line E::first-letter E::before E::after E.warning E#myid E:not(s) E F E > F E + F E ~ F

含义 ------------------------------------- 任 何元素 类型为E的元素 匹配具有foo属性的元素E 匹配foo属性值为bar的元素E 匹配 foo属性值是空格分隔的多值情况时，有一个值为bar的元素E 匹配foo属性值以bar开头的元素E 匹配foo属性值以bar结尾的元 素E 匹配foo属性值中包含字符串bar的元素E 匹配foo属性值包括带有连字符“-”的情况，以en开头的元素E 文档的根元素 E 父元素中的第n个子元素E 父元素中的倒数第n个子元素E 此类型中第n个同级兄弟元素E 此类型中倒数第n个 同级兄弟元素E 父元素中首个子元素E 父元素中最后一个子元素E 此类型中首个同级兄弟元素E 此类型中最后一 个同级兄弟元素E 父元素的子元素E 此类型的同级兄弟元素E 匹配没有任何子元素（包括文本节点）的元素E 匹配具有超链接源 锚点的元素E 没有被访问（:link） 或者已经访问（:visited） 匹配元素E具有的某 些用户操作 匹配具有目标URI引用的元素E 匹配具有特定语言fr的元素E（文档语言指定了文档采用什么语言） 匹 配启用或者禁用状态的元素E 匹配处于被选中状态的元素E（比如，一个单选按钮或复选框） 匹配元素E的首行格式化 匹 配元素E的首字符格式化 匹配元素E的前面生成的内容 匹配元素E的后面生成的内容 匹配class属性是warning的元素E（文 档语言指定了class怎样被确定） 匹配id属性为myid的元素E 不匹配简单选择器s的元素E 匹配元素F是元素E的后代 匹 配元素F是元素E的子元素 匹配元素F的前面是元素E 匹配元素F的前面有元素E

说明（CSS版本） ---------------------------------- 通用选择器（2） 类型选择器（1） 属性选择器（2） 属 性选择器（2） 属性选择器（2） 属性选择器（3） 属 性选择器（3） 属性选择器（3） 属性选择器（2） 结构性伪类（3） 结 构性伪类（3） 结构性伪类（3） 结构性 伪类（3） 结构性伪类（3） 结 构性伪类（2） 结构性伪类（3） 结 构性伪类（3） 结构 性伪类（3） 结 构性伪类（3） 结 构性伪类（3） 结 构性伪类（3） 链接伪类（1） 用户操作伪类（1 和2） 目标伪类（3） :lang()伪类（2） 用户界面元素状态伪类（3） 用 户界面元素状态伪类（3） ::first-line伪类（1） ::first-letter伪 类（1） ::before伪类（2） ::after伪类（2） Class选择器（1） ID选择器（1） 否定伪类（3） 后代组合（1） 子组合（2） 相 邻兄弟组合（2） 同 级兄弟组合（3）

附一个CSS3选择器链接：http://www.web600.net/tool/css3_0/attribute_selectors.shtml

This section is non-normative, as it merely summarizes the following sections.

A Selector represents a structure. This structure can be used as a condition (e.g. in a CSS rule) that determines which elements a selector matches in the document tree, or as a flat description of the HTML or XML fragment corresponding to that structure.

Selectors may range from simple element names to rich contextual representations.

The following table summarizes the Selector syntax:

Pattern	Meaning	Described in section	First defined in CSS level
*	any element	Universal selector	2
E	an element of type E	Type selector	1
E[foo]	an E element with a "foo" attribute	Attribute selectors	2
E[foo="bar"]	an E element whose "foo" attribute value is exactly equal to "bar"	Attribute selectors	2
E[foo~="bar"]	an E element whose "foo" attribute value is a list of space-separated values, one of which is exactly equal to "bar"	Attribute selectors	2
E[foo^="bar"]	an E element whose "foo" attribute value begins exactly with the string "bar"	Attribute selectors	3
E[foo$="bar"]	an E element whose "foo" attribute value ends exactly with the string "bar"	Attribute selectors	3
E[foo*="bar"]	an E element whose "foo" attribute value contains the substring "bar"	Attribute selectors	3
E[hreflang|="en"]	an E element whose "hreflang" attribute has a hyphen-separated list of values beginning (from the left) with "en"	Attribute selectors	2
E:root	an E element, root of the document	Structural pseudo-classes	3
E:nth-child(n)	an E element, the n-th child of its parent	Structural pseudo-classes	3
E:nth-last-child(n)	an E element, the n-th child of its parent, counting from the last one	Structural pseudo-classes	3
E:nth-of-type(n)	an E element, the n-th sibling of its type	Structural pseudo-classes	3
E:nth-last-of-type(n)	an E element, the n-th sibling of its type, counting from the last one	Structural pseudo-classes	3
E:first-child	an E element, first child of its parent	Structural pseudo-classes	2
E:last-child	an E element, last child of its parent	Structural pseudo-classes	3
E:first-of-type	an E element, first sibling of its type	Structural pseudo-classes	3
E:last-of-type	an E element, last sibling of its type	Structural pseudo-classes	3
E:only-child	an E element, only child of its parent	Structural pseudo-classes	3
E:only-of-type	an E element, only sibling of its type	Structural pseudo-classes	3
E:empty	an E element that has no children (including text nodes)	Structural pseudo-classes	3
E:link E:visited	an E element being the source anchor of a hyperlink of which the target is not yet visited (:link) or already visited (:visited)	The link pseudo-classes	1
E:active E:hover E:focus	an E element during certain user actions	The user action pseudo-classes	1 and 2
E:target	an E element being the target of the referring URI	The target pseudo-class	3
E:lang(fr)	an element of type E in language "fr" (the document language specifies how language is determined)	The :lang() pseudo-class	2
E:enabled E:disabled	a user interface element E which is enabled or disabled	The UI element states pseudo-classes	3
E:checked	a user interface element E which is checked (for instance a radio-button or checkbox)	The UI element states pseudo-classes	3
E::first-line	the first formatted line of an E element	The ::first-line pseudo-element	1
E::first-letter	the first formatted letter of an E element	The ::first-letter pseudo-element	1
E::selection	the portion of an E element that is currently selected/highlighted by the user	The UI element fragments pseudo-elements	3
E::before	generated content before an E element	The ::before pseudo-element	2
E::after	generated content after an E element	The ::after pseudo-element	2
E.warning	an E element whose class is "warning" (the document language specifies how class is determined).	Class selectors	1
E#myid	an E element with ID equal to "myid".	ID selectors	1
E:not(s)	an E element that does not match simple selector s	Negation pseudo-class	3
E F	an F element descendant of an E element	Descendant combinator	1
E > F	an F element child of an E element	Child combinator	2
E + F	an F element immediately preceded by an E element	Adjacent sibling combinator	2
E ~ F	an F element preceded by an E element	General sibling combinator	3

The meaning of each selector is derived from the table above by prepending "matches" to the contents of each cell in the "Meaning" column.