jQuery滑出效果的下拉菜单导航

为你的基础上创建一个无序列表导航。然后简单的嵌套另一个无序列表子导航。
<ul class="topnav">
    <li><a href="#">Home</a></li>
    <li>
        <a href="#">Tutorials</a>
        <ul class="subnav">
            <li><a href="#">Sub Nav Link</a></li>
            <li><a href="#">Sub Nav Link</a></li>
        </ul>
    </li>
    <li>
        <a href="#">Resources</a>
        <ul class="subnav">
            <li><a href="#">Sub Nav Link</a></li>
            <li><a href="#">Sub Nav Link</a></li>
        </ul>
    </li>
    <li><a href="#">About Us</a></li>
    <li><a href="#">Advertise</a></li>
    <li><a href="#">Submit</a></li>
    <li><a href="#">Contact Us</a></li>
</ul>
接下来,CSS样式的导航线框图。
ul.topnav {
 list-style: none;
 padding: 0 20px;
 margin: 0;
 float: left;
 width: 920px;
 background: #222;
 font-size: 1.2em;
 background: url(topnav_bg.gif) repeat-x;
}
ul.topnav li {
 float: left;
 margin: 0;
 padding: 0 15px 0 0;
 position: relative; /*--Declare X and Y axis base for sub navigation--*/
}
ul.topnav li a{
 padding: 10px 5px;
 color: #fff;
 display: block;
 text-decoration: none;
 float: left;
}
ul.topnav li a:hover{
 background: url(topnav_hover.gif) no-repeat center top;
}
ul.topnav li span { /*--Drop down trigger styles--*/
 width: 17px;
 height: 35px;
 float: left;
 background: url(subnav_btn.gif) no-repeat center top;
}
ul.topnav li span.subhover {background-position: center bottom; cursor: pointer;} /*--Hover effect for trigger--*/
ul.topnav li ul.subnav {
 list-style: none;
 position: absolute; /*--Important - Keeps subnav from affecting main navigation flow--*/
 left: 0; top: 35px;
 background: #333;
 margin: 0; padding: 0;
 display: none;
 float: left;
 width: 170px;
 border: 1px solid #111;
}
ul.topnav li ul.subnav li{
 margin: 0; padding: 0;
 border-top: 1px solid #252525; /*--Create bevel effect--*/
 border-bottom: 1px solid #444; /*--Create bevel effect--*/
 clear: both;
 width: 170px;
}
html ul.topnav li ul.subnav li a {
 float: left;
 width: 145px;
 background: #333 url(dropdown_linkbg.gif) no-repeat 10px center;
 padding-left: 20px;
}
html ul.topnav li ul.subnav li a:hover { /*--Hover effect for subnav links--*/
 background: #222 url(dropdown_linkbg.gif) no-repeat 10px center;
}
步骤3。jQuery
下面的脚本包含注释解释jQuery行动正在进行。

$(document).ready(function(){
 
 $("ul.subnav").parent().append("<span></span>"); //Only shows drop down trigger when js is enabled (Adds empty span tag after ul.subnav*)
 
 $("ul.topnav li span").click(function() { //When trigger is clicked...
 
  //Following events are applied to the subnav itself (moving subnav up and down)
  $(this).parent().find("ul.subnav").slideDown('fast').show(); //Drop down the subnav on click
 
  $(this).parent().hover(function() {
  }, function(){
   $(this).parent().find("ul.subnav").slideUp('slow'); //When the mouse hovers out of the subnav, move it back up
  });
 
  //Following events are applied to the trigger (Hover events for the trigger)
  }).hover(function() {
   $(this).addClass("subhover"); //On hover over, add class "subhover"
  }, function(){ //On Hover Out
   $(this).removeClass("subhover"); //On hover out, remove class "subhover"
 });
 
});