目录
- 鼠标经过展开下拉菜单[ul]方法一
- 方法二
[/ul]
鼠标经过展开下拉菜单
方法一
<!DOCTYPE html><html lang=\"en\"> <head> <meta charset=\"UTF-8\" /> <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\" /> <title>js实现下拉二级菜单</title> <style> * { margin: 0px; padding: 0px; } body { font-family: Verdana, Geneva, sans-serif; font-size: 14px; } #nav { width: 600px; height: 40px; background-color: #eee; margin: 0 auto; } ul { list-style: none; } ul li { float: left; line-height: 40px; text-align: center; width: 100px; /*ie7显示宽度的兼容性 设置width 而不用padding的自适应 */ } a { text-decoration: none; color: #000; display: block; } a:hover { color: #f00; background-color: #666; } ul li ul li { float: none; background-color: #eee; margin: 2px 0px; } ul li ul { display: none; } </style> </head> <body> <div id=\"nav\"> <ul> <li><a href=\"#\">首页</a></li> <li onmouseover=\"ShowSub(this)\" onmouseout=\"HideSub(this)\"> <a href=\"#\">课程大厅</a> <ul> <li><a href=\"#\">JavaScript</a></li> <li><a href=\"#\">Html/CSS</a></li> </ul> </li> <li onmouseover=\"ShowSub(this)\" onmouseout=\"HideSub(this)\"> <a href=\"#\">学习中心</a> <ul> <li><a href=\"#\">视频学习</a></li> <li><a href=\"#\">实例练习</a></li> <li><a href=\"#\">问与答</a></li> </ul> </li> <li><a href=\"#\">经典案例</a></li> <li><a href=\"#\">关于我们</a></li> </ul> </div> <script> function ShowSub(li) { //函数定义 var subMenu = li.getElementsByTagName(\"ul\")[0]; //获取 subMenu.style.display = \" block \"; } function HideSub(li) { var subMenu = li.getElementsByTagName(\"ul\")[0]; subMenu.style.display = \" none \"; } </script> </body></html>
方法二
<!DOCTYPE html><html lang=\"en\"><head> <meta charset=\"UTF-8\"> <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\"> <style type=\"text/css\"> * { margin: 0px; } a{ text-decoration: none; font-size: 16px; color: #333; } #nav { width: 700px; height: 40px; background: #ddd; margin: 20px auto; } #nav ul { list-style: none; } #nav ul li { width: 120px; float: left; } #nav ul li a { display: block; text-align: center; line-height: 40px; } #nav ul li a:hover { background: #CCCCDD; } #nav ul li div { font-size: 18px; display: none; } #nav ul li div a { line-height: 40px; text-align: center; background: #ddd; } #nav ul li div a:hover { background: #FF9090; } </style></head><body> <div id=\"nav\"> <ul> <li> <a href=\"#\">首页</a> </li> <li> <a href=\"#\">课程大厅</a> <div> <a href=\"#\">JavaScript</a> <a href=\"#\">html/css</a> <a href=\"#\">Bootstrap</a> </div> </li> <li> <a href=\"\">学习中心</a> <div> <a href=\"#\">视频中心</a> <a href=\"#\">实例练习</a> <a href=\"#\">问与答</a> </div> </li> <li><a href=\"#\">经典案例</a></li> <li><a href=\"#\">关于我们</a></li> </ul> </div> <script type=\"text/javascript\"> window.onload = function () { var aLi = document.getElementById(\"nav\").getElementsByTagName(\"li\"); for (var i = 0; i < aLi.length; i++) { aLi[i].onmouseover = function () { if( this.children[1]){ this.children[1].style.display = \'block\';//选取当前li元素的第二个子元素 } } aLi[i].onmouseout = function () { if( this.children[1]){ this.children[1].style.display = \'none\'; } } } } </script></body></html>