在css森林群裡討論一個margin的問題中無意間發現overflow也可以用來清除浮動,嘿嘿,這個方法不單使用簡單,而且ff、op、ie7都支持,從此可以告別那又長兼容性又差的ff清浮動的方法了。
方法真的很簡單,只要為需要清除浮動的標籤加上overflow這個屬性。
css程式碼
ul { list-style: none; height: auto; margin: 0; p adding: 0; background-color: #436973; } li { float: left; width: 80px; height: 80px; background-color: #83b1df; } .demo { clear: both; border: 1px solid #ff00ff; margin-bottom: 5px; } .overflow { overflow: auto; zoom: 1; background-color: #43ff73; } ul { list-style: none; height: auto; margin: 0; padding: 0; background-color: #436973; } li { float: left; width: 80px; height: 80px; background-color: #83b1df; } .demo { clear: both; border: 1px solid #ff00ff; margin-bottom: 5px; } .overflow { overflow: auto; zoom: 1; background-color: #43ff73; }
html程式碼
<div class="demo"> <ul class="overflow"> <li>1</li> <li>2</li> <li>3</li> <li>4</li> <li>5</li> <li>6</li> <li>7</li> <li>8</li> <li>9</li> </ul> </div> <div class="demo"> <ul> <li>1</li> <li>2</li> <li>3</li> <li>4</li> <li>5</li> <li>6</li> <li>7</li> <li>8</li> <li>9</li> </ul> </div>
其中zoom是為了ie6準備的。
<?xml version="1.0" encoding="utf-8"?> <!doctype html public "-//w3c//dtd xhtml 1.0 strict//en" "http://www.w3.org/tr/xhtml1/dtd/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh-cn"> <head> <meta http-equiv="pragma" content="no-cache" /> <meta http-equiv="content-type" content="text/html; charset=utf-8" /> <meta http-equiv="content-language" content="utf-8" /> <meta name="robots" content="all" /> <meta name="author" content="ghost" /> <meta name="copyright" content="cssforest" /> <meta name="description" content="cssɭ" /> <meta name="keywords" content="css,web标准,web,blog,,xhtml,cssforest,css森林" /> <title>overflow hack demo|www.cssforest.org</title> <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" /> <script src="http://www.google-analytics.com/urchin.js" type="text/javascript"></script> <script type="text/javascript">_uacct = "ua-780254-5";urchintracker();</script> <style type="text/css"> /*<![cdata[*/ .copyright{position:absolute;bottom:60px;left:10px;width:300px;height:200px;line-height:1.2em;} .copyright a:link{color:#666666;text-decoration:none;} .copyright a:hover{color:#cc9900;text-decoration:underline;} ul{list-style:none;height:auto;margin:0;padding:0;background-color:#436973;} li{float:left;width:80px;height:80px;background-color:#83b1df;} .demo{clear:both;border:1px solid #ff00ff;margin-bottom:5px;} .overflow{overflow:auto;zoom:1;background-color:#43ff73;} /*]]>*/ </style> </head> <body> <p></p> <div> <ul> <li>1</li> <li>2</li> <li>3</li> <li>4</li> <li>5</li> <li>6</li> <li>7</li> <li>8</li> <li>9</li> </ul> </div> <div> <ul> <li>1</li> <li>2</li> <li>3</li> <li>4</li> <li>5</li> <li>6</li> <li>7</li> <li>8</li> <li>9</li> </ul> </div> <div> <div> <div><img src="http://img68.imageshack.us/img68/8708/mycss對於IE7、FF、OP清除浮動的最優方法9we.gif" alt="css對於IE7、FF、OP清除浮動的最優方法" /></div> <div> <p class="fn n"><strong>ghost</strong> <strong>zhang</strong></p> <p><strong>email:</strong><a href="mailto:lovej1bz@gmail.com">lovej1bz@gmail.com</a></p> <p><strong>qq:</strong><a href="tencent://message/?uin=22168741&site=webrebuild.org&menu=yes">22168741</a></p> <p><strong>org:</strong><a href="http://www.webrebuild.org">webrebuild.org</a> <a href="http://www.cssforest.org/">www.cssforest.org</a></p> <strong>blog:</strong><a href="http://forest.blogbus.com" rel="me">http://forest.blogbus.com</a> </div> </div> </div> </body> </html>
註:忘了一個很重要的內容,並不是所有的overflow屬性都可起來一樣的效果,例如visible屬性就只能對ie起作用。例子可以看這裡:
<?xml version="1.0" encoding="utf-8"?> <!doctype html public "-//w3c//dtd xhtml 1.0 strict//en" "http://www.w3.org/tr/xhtml1/dtd/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh-cn"> <head> <meta http-equiv="pragma" content="no-cache" /> <meta http-equiv="content-type" content="text/html; charset=utf-8" /> <meta http-equiv="content-language" content="utf-8" /> <meta name="robots" content="all" /> <meta name="author" content="ghost" /> <meta name="copyright" content="cssforest" /> <meta name="description" content="cssɭ" /> <meta name="keywords" content="css,web标准,web,blog,,xhtml,cssforest,css森林" /> <title>overflow hack demo|www.cssforest.org</title> <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" /> <script src="http://www.google-analytics.com/urchin.js" type="text/javascript"></script> <script type="text/javascript">_uacct = "ua-780254-5";urchintracker();</script> <style type="text/css"> /*<![cdata[*/ .copyright{position:absolute;bottom:60px;left:10px;width:300px;height:200px;line-height:1.2em;} .copyright a:link{color:#666666;text-decoration:none;} .copyright a:hover{color:#cc9900;text-decoration:underline;} ul{list-style:none;height:auto;margin:0;padding:0;background-color:#436973;} li{float:left;height:80px;margin-right:2px;padding:0 10px;background-color:#83b1df;line-height:80px;} .demo{clear:both;border:1px solid #ff00ff;margin-bottom:5px;} .overflow{overflow:auto;zoom:1;background-color:#43ff73;} .overflow1{overflow:hidden;zoom:1;background-color:#43ff73;} .overflow2{overflow:visible;zoom:1;background-color:#43ff73;} /*]]>*/ </style> </head> <body> <p>overflow的visible属性只对ie起作用,auto/hidden可对ff、op起作用。</p> <div> <ul> <li>overflow:auto;</li> <li>overflow:auto;</li> <li>overflow:auto;</li> <li>overflow:auto;</li> <li>overflow:auto;</li> <li>overflow:auto;</li> </ul> </div> <div> <ul> <li>overflow:hidden;</li> <li>overflow:hidden;</li> <li>overflow:hidden;</li> <li>overflow:hidden;</li> <li>overflow:hidden;</li> <li>overflow:hidden;</li> </ul> </div> <div> <ul> <li>overflow:visible;</li> <li>overflow:visible;</li> <li>overflow:visible;</li> <li>overflow:visible;</li> <li>overflow:visible;</li> <li>overflow:visible;</li> </ul> </div> <div> <ul> <li>no overflow</li> <li>no overflow</li> <li>no overflow</li> <li>no overflow</li> <li>no overflow</li> <li>no overflow</li> </ul> </div> <div> <div> <div><img src="http://img68.imageshack.us/img68/8708/mycss對於IE7、FF、OP清除浮動的最優方法9we.gif" alt="css對於IE7、FF、OP清除浮動的最優方法" /></div> <div> <p class="fn n"><strong>ghost</strong> <strong>zhang</strong></p> <p><strong>email:</strong><a href="mailto:lovej1bz@gmail.com">lovej1bz@gmail.com</a></p> <p><strong>qq:</strong><a href="tencent://message/?uin=22168741&site=webrebuild.org&menu=yes">22168741</a></p> <p><strong>org:</strong><a href="http://www.webrebuild.org">webrebuild.org</a> <a href="http://www.cssforest.org/">www.cssforest.org</a></p> <strong>blog:</strong><a href="http://forest.blogbus.com" rel="me">http://forest.blogbus.com</a> </div> </div> </div> </body> </html>
這樣的話就有一個問題啦,如果要有高度,而且內容超出高度的時候,定義auto或hidden都可能會有一些不想要的效果出現。這裡提供一個解決方案:對於ie6以下版本的ie,可以直接定義高度;對於ie7、ff、op,可定義min-height。
css代碼:
overflow { height:auto; _height:200px; min-height:200px; verflow:auto; zoom:1; _overflow:visible; }