nav-down · CSS 3.0參考手冊.chm

# nav-down **版本：CSS3** ### 語法： **nav-down** ： auto | <id>[ current | root | <target-name> ]? | inherit **相關屬性** ： [nav-index](#) , [nav-up](#) , [nav-right](#) , [nav-down](#) ### 取值： auto：User Agent默認的順序。<id> ：要切換元素的id命名。root | <target-name>：這個參數不能以”_”命名，指出frameset目標頁面之間的元素焦點切換。如果指定的目標頁面不存在，則被視為當前頁面的焦點，意味著完全依賴框架頁。該屬性是以關鍵節點”root”標示，User agent將把整個frameset框架頁定為目標。inherit：默認繼承。 ### 說明：輸入設備默認四個方向鍵按html文檔順序順序來控制元素的焦點切換，但為了更好的用戶體驗，User agents提供了自定義切換焦點的控制順序方向。 ### 兼容性： <table><thead><tr><th class="type">類型</th> <th class="type_ie"><img src="https://box.kancloud.cn/2015-09-02_55e5d388c7d74.png" alt="IE" />Internet Explorer</th> <th class="type_firefox"><img src="https://box.kancloud.cn/2015-09-02_55e5d388d0d7f.png" alt="Firefox" />Firefox</th> <th class="type_chrome"><img src="https://box.kancloud.cn/2015-09-02_55e5d388d7e1e.png" alt="Chrome" />Chrome</th> <th class="type_opera"><img src="https://box.kancloud.cn/2015-09-02_55e5d388e168e.png" alt="Opera" />Opera</th> <th class="type_safari"><img src="https://box.kancloud.cn/2015-09-02_55e5d388e959c.png" alt="Safari" />Safari</th> </tr></thead><tbody><tr><td rowspan="4" class="version">版本</td> <td class="support yes"><span>(√)</span>IE6</td> <td class="support no"><span>(×)</span>Firefox 2.0</td> <td class="support yes"><span>(√)</span>Chrome 1.0.x</td> <td class="support yes"><span>(√)</span>Opera 9.63</td> <td class="support yes"><span>(√)</span>Safari 3.1</td> </tr><tr><td class="support yes"><span>(√)</span>IE7</td> <td class="support yes"><span>(√)</span>Firefox 3.0</td> <td class="support yes"><span>(√)</span>Chrome 2.0.x</td> <td></td> <td class="support yes"><span>(√)</span>Safari 4Public beta</td> </tr><tr><td class="support yes"><span>(√)</span>IE8</td> <td class="support yes"><span>(√)</span>Firefox 3.5</td> <td></td> <td></td> <td></td> </tr><tr><td></td> <td></td> <td></td> <td></td> <td></td> </tr></tbody></table> ### 示例： <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title>nav_相關屬性測試</title></head><style>button { position:absolute; }button#b1 { top:0; left:50%; nav-index:1;nav-right:#b2; nav-left:#b4;nav-down:#b2; nav-up:#b4;}button#b2 { top:50%; left:100%; nav-index:2;nav-right:#b3; nav-left:#b1;nav-down:#b3; nav-up:#b1;}button#b3 { top:100%; left:50%; nav-index:3;nav-right:#b4; nav-left:#b2;nav-down:#b4; nav-up:#b2;}button#b4 { top:50%; left:0; nav-index:4;nav-right:#b1; nav-left:#b3;nav-down:#b1; nav-up:#b3;}</style><body> <button id="b1">BT1</button> <button id="b2">BT2</button> <button id="b3">BT3</button> <button id="b4">BT4</button></body></html> 復制代碼 Copyright ? 2009 [Tencent ISD webteam](http://webteam.tencent.com/). All Rights Reserved ### 快速跳轉 - [語法](# "跳轉到“語法”") - [取值](# "跳轉到“取值”") - [說明](# "跳轉到“說明”") - [兼容性](# "跳轉到“兼容性”") - [示例](# "跳轉到“示例”")