鼠标悬浮显示二级菜单效果的jquery实现_jquery

1.布局：

2.js控制：

function dropMenu(obj) { 
$(obj).each(function () { 
var theSpan = $(this); 
var theMenu = theSpan.find(".drop"); 
var tarHeight = theMenu.height(); 
theMenu.css({ height: 0, opacity: 0 }); 


var t1; 


function expand() { 
clearTimeout(t1); 
//theSpan.find('a').addClass("selected"); 
theMenu.stop().show().animate({ height: tarHeight, opacity: 1 }, 200); 
} 


function collapse() { 
clearTimeout(t1); 
t1 = setTimeout(function () { 
// theSpan.find('a').removeClass("selected"); 
theMenu.stop().animate({ height: 0, opacity: 0 }, 200, function () { 
$(this).css({ display: "none" }); 
}); 
}, 250); 
} 


theSpan.hover(expand, collapse); 
theMenu.hover(expand, collapse); 
}); 
}