繁體中文当前位置: 首页 > 图文教程 > 网页制作 > CSS样式表 > 英文教程:五种CSS选择器类型
- CSS样式表
- Web设计中的黄金分割分析
- 简单的CSS 下拉导航菜单实现代码
- Float 菜单水平居中简单方法
- 网页设计中常用的19个Web安全字体
- 网页设计中的中国传统色彩速查表 颜色值
- css 清除浮动的新方法
- CSS 字体单位em简介
- CSS下10个节约开发时间的技巧
- css 等宽导航栏设计技巧
- CSS reflow实例教程
- IE6下Select元素被div等元素覆盖的解决办法
- 需要知道的CSS3动画技术
- 一个很有用的Firefox和IE插件
- IE6,IE7下实现white-space:pre-wrap
- CSS 圆角框进行JS封装版
- 基于链接关系的微格式 使用rel属性
- css 微格式 XFN规范
- 网页简历结构和语义信息 hResume微格式
- hCalendar微格式 关于事件和基于时间或地点的活
- CSS下!important属性
CSS样式表 中的 英文教程:五种CSS选择器类型
出处:互联网 整理: 软晨网（RuanChen.com） 发布: 2009-09-11 浏览: 201 ::
收藏到网摘: n/a
英文教程:五种CSS选择器类型. CSScommandsareusuallygroupedinthecurlybracestomakeasetofrules.FollowingarethevariouswaysavailabletoattachthesesetofruleswithHTMLcode.
Selector(insimplewords)meanshowyounamethesesetofrules.
1CLASSSelectORS
ClassselectorsisthesimplestformofselectorswhereyouassignyourownmeaningfulnametothesetofCSSrules.Tocreateaclassselectoryousimplyneedtowritenameoftheclassfollowedbyaperiod.
(Aclassnamecannotstartwithanumberorasymbolasitisnotsupportedbyvariousbrowsers.)
Forexample,
p.big{font-weight:bold;font-size:12px;}
.center{text-align:center;}
AndthisHTML:
<pclass="big">Thisparagraphwillberenderedbold.www.ruanchen.com</p>
Youcanapplymorethanoneclasstoagivenelement.
AndthisHTML:
<pclass="centerbig">Thisparagraphwillberenderedbold.</p>
Intheaboveexample.bigand.centerarenameofCSSclassesandtheseclassesareappliedtoPtaginHTML.
IfclassnameisfollowedbyHTMLelementinyourCSScodelikep.biginaboveexampleitmeansthatthisclasswillworkonPtagonly.
OtherwiseyoucanapplytheCSSclassonanyelement.
It’sagoodpracticetoaddHTMLelementbeforeclassnameinCSSifyouarewritingCSSrulesforaparticularelement(ItaddsmoreclaritytoCSScode.
2IDSelectORS
IDselectorsworklikeclassselectors,exceptthattheycanonlybeusedononeelementperpagebecausetheyworkwithIDofthehtmlelement.TheidselectorisdefinedasidoftheHTMLelementfollowedbya#symbol.
Forexample,
p#navigation{width:12em;color:#666;font-weight:bold;}
AndthisHTML:
<pid="navigation">Thisparagraphwillberenderedbold.www.ruanchen.com</p>
AsagoodpracticeIDselectorsmustbeusedifyouarewritingtheCSScodeforasingleHTMLelementonly.IDselectorsarewellsupportedacrossstandards-compliantbrowsers.
3TAGSelectOR
TagselectorisanothersimplemethodofCSSrulesimplementation.YoucanusethisselectortoredefinetherulesforaparticularHTMLelement.
Forexample:
p{color:#999;font-weight:bold;}
IntheaboveexampleCSScodewillbeautomaticallyappliedoneveryptag.
4DESCENDENTSelectORS
Descendentselectorsspecifythatstylesshouldonlybeappliedwhentheelementinquestionisadescendent(forexample,achild,oragrandchild)ofanotherelement.
Forexample,
h3em{color:white;background-color:black;}
AndthisHTML:
<h3>Thisis<em>emphasized</em>www.ruanchen.com</h3>
Intheaboveexampleemisdescendentofh3element.Abovecssrulewillautomaticallybeappliedonallemelementsinsideh3elementintheHTMLcode.Descendentselectorsarewellsupportedacrossstandards-compliantbrowsers.
5GROUPINGSelectORS
Youcanalsospecifythesamesetofrulesformorethanoneselctor,likethis:
p,h1,h2{text-align:left;}
Justplaceacommabetweeneachone.
Youcanevengetmorecomplex,andgroupmultipleclassandidselectors:
p.navigation,h1#title{font-weight:bold;}
评论 (0) All
