IE6、IE7不支持二级子ul的问题

今天遇到一个在ul下增加子ul的问题，

先贴html代码：

<ul id="leftnav"><li class="leftnav-item" id="leftnav1" data-index="1"><img src="../../static/zt/gamedata_ppsg/01.jpg" alt="了解游戏"><b class="leftnav-layer" id="leftnav-layer1"></b></li><li class="leftnav-item" id="leftnav2" data-index="2"><img src="../../static/zt/gamedata_ppsg/02.jpg" alt="基础资料"><b class="leftnav-layer" id="leftnav-layer2"></b></li><ul class="gamedata-list"><li class="gamedata-item"><span>部队系统</span><b class="gamedata-layer" id="gamedata-layer1"></b></li><li class="gamedata-item"><span>卡片系统</span><b class="gamedata-layer" id="gamedata-layer2"></b></li><li class="gamedata-item"><span>科技系统</span><b class="gamedata-layer" id="gamedata-layer3"></b></li><li class="gamedata-item"><span>分解系统</span><b class="gamedata-layer" id="gamedata-layer4"></b></li><li class="gamedata-item"><span>升级系统</span><b class="gamedata-layer" id="gamedata-layer5"></b></li></ul><li class="leftnav-item" id="leftnav3" data-index="3"><img src="../../static/zt/gamedata_ppsg/03.jpg" alt="起始武将"><b class="leftnav-layer" id="leftnav-layer3"></b></li></ul>

采用上述结构的原因是起初二级ul放在父li里面的话会影响hover浮层效果覆盖的区域：浮层会将二级ul全部罩住，影响鼠标点击二级菜单操作。所以就把二级ul拿出来放在li外了。可是这样ie7下就不显示二级ul了。

对应CSS代码：

#leftnav{position:absolute;z-index:9;left:10px ;top:10px;border: 1px solid #c8c2c0;width: 240px;overflow: hidden;border-bottom: none;}.leftnav-item{position:relative;width: 100%;height: 98px;border-bottom: 1px solid #c8c2c0;float: left;cursor: pointer;}#leftnav1{}.leftnav-layer{display:block;position: absolute;left: 0;top: 0;width: 100%;height: 98px;bottom:98px;}.cur,.leftnav-layer:hover{background-color: #000;-webkit-opacity:0.3 ;-moz-opacity: 0.3;-o-opacity:0.3;opacity: .3;-ms-filter:"progid:DXImageTransform.Microsoft.Alpha(Opacity=30)";filter: alpha(opacity=30);}.gamedata-list{float:left;background: url("../../zt/gamedata_ppsg/data.png") no-repeat 0 0 transparent;width:240px;height: 342px;}#leftnav2{height: 440px;}.gamedata-item{cursor:pointer;position:relative;padding:1px 0;height: 65px;line-height:65px;float: left;padding-left: 90px;font-size: 27px;color: #fff;}.gamedata-layer{position: absolute;left: 18px;top: 5px;width: 200px;height: 100%;}.sel,.gamedata-layer:hover {/*position: absolute;left: 18px;top: 5px;width: 200px;height: 65px;*/background:url("blank");background-image: -webkit-gradient(linear, 0 0, 0 100%, from(rgba(255,255,255,.5)), to(rgba(255,255,255,0)));background-image: -webkit-linear-gradient(top,rgba(255,255,255,.5), rgba(255,255,255,0));background-image: -moz-linear-gradient(top,rgba(255,255,255,.5), rgba(255,255,255,0));background-image: -o-linear-gradient(top,rgba(255,255,255,.5), rgba(255,255,255,0));background-image: linear-gradient(top,rgba(255,255,255,.5), rgba(255,255,255,0));background-image: linear-gradient(to bottom,rgba(255,255,255,.5), rgba(255,255,255,0));-ms-filter: "progid:DXImageTransform.Microsoft.gradient(GradientType=0,startColorstr=#50ffffff,endColorstr=#00ffffff)"; /*Filter for IE8 */    filter: progid:DXImageTransform.Microsoft.gradient(GradientType=0,startColorstr=#50ffffff, endColorstr=#00ffffff); /*Filter for older IEs */}

在IE6和IE7下子ul.gamedata-list诡异的隐藏起来不显示了。效果如图

而在标准浏览器里是这样的效果：

查阅发现这种ul > ul结构可能是不合规范，确实是IE6-7下的解析兼容问题，国外有建议将此二级结构放在table布局里用td分隔开以防止解析错误。对于我是不太愿意使用这种蹩脚的方法，更愿意从根本上从CSS或调整结构入手。有人说用dl > dd代替二级ul可以回避这个问题，有兴趣的可以试一下。

多次尝试使用CSS来解决但发现无效，对IE6-7太顽固了。

最后只能将结构改回原来的在li下放ul形式。

 

原来存在的问题是因为只有IE7+才支持任何元素的:hover伪类，所以抛弃了这个即将过时的IE6的hover效果，后来发现自己写的jquery click和mouseover效果有局限性：只有点在浮层上才能触发click效果。故而将二级ul列表的b标签更改为a标签，且对要hover的容器换成a标签以支持ie6，另外对a链接加以href属性，否则IE6-8也是无法展示鼠标移上的效果的，这样以兼容所有浏览器下的菜单点击切换对应的内容。

 

修改后的结构如下所示：

<ul id="leftnav"><li class="leftnav-item" id="leftnav1" data-index="1"><a class="leftnav-layer" id="leftnav-layer1"  href="javascript:void(0);"><img src="../../static/zt/gamedata_ppsg/01.jpg" alt="了解游戏"></a></li><li class="leftnav-item" id="leftnav2" data-index="2"><a  href="javascript:void(0);" class="leftnav-layer" id="leftnav-layer2"><img src="../../static/zt/gamedata_ppsg/02.jpg" alt="基础资料"><!-- <b class="leftnav-layer" id="leftnav-layer2"></b> --></a><ul class="gamedata-list"><li class="gamedata-item"><span>部队系统</span><a href="javascript:void(0);" class="gamedata-layer" id="gamedata-layer1"></a></li><li class="gamedata-item"><span>卡片系统</span><a href="javascript:void(0);" class="gamedata-layer" id="gamedata-layer2"></a></li><li class="gamedata-item"><span>科技系统</span><a href="javascript:void(0);" class="gamedata-layer" id="gamedata-layer3"></a></li><li class="gamedata-item"><span>分解系统</span><a href="javascript:void(0);" class="gamedata-layer" id="gamedata-layer4"></a></li><li class="gamedata-item"><span>升级系统</span><a href="javascript:void(0);" class="gamedata-layer" id="gamedata-layer5"></a></li></ul></li><li class="leftnav-item" id="leftnav3" data-index="3"><a class="leftnav-layer" id="leftnav-layer3" href="javascript:void(0);"><img src="../../static/zt/gamedata_ppsg/03.jpg" alt="起始武将"></a></li></ul>

新修改后的CSS样式代码：

#leftnav{position:absolute;z-index:9;left:10px ;top:10px;border: 1px solid #c8c2c0;width: 240px;overflow: hidden;border-bottom: none;}.leftnav-item{position:relative;width: 100%;height: 98px;border-bottom: 1px solid #c8c2c0;float: left;cursor: pointer;}.leftnav-layer{display:block;width: 240px;height: 98px;}.cur, .leftnav-item a:hover{background-color: #000;-webkit-opacity:0.3 ;-moz-opacity: 0.3;-o-opacity:0.3;opacity: .3;-ms-filter:"progid:DXImageTransform.Microsoft.Alpha(Opacity=30)";filter:progid:DXImageTransform.Microsoft.Alpha(Opacity=30);filter: alpha(opacity=30);}.gamedata-list{float:left;background: url("../../zt/gamedata_ppsg/data.png") no-repeat 0 0 transparent;width:240px;height: 342px;}#leftnav2{height: 440px;}.gamedata-item{cursor:pointer;position:relative;padding:1px 0;height: 65px;line-height:65px;float: left;padding-left: 90px;font-size: 27px;color: #fff;}.gamedata-layer{position: absolute;left: 18px;top: 5px;width: 200px;height: 100%;}.sel,.gamedata-item a.gamedata-layer:hover {position: absolute;left: 18px;top: 5px;width: 200px;height: 65px;background:url("blank");background-image: -webkit-gradient(linear, 0 0, 0 100%, from(rgba(255,255,255,.5)), to(rgba(255,255,255,0)));background-image: -webkit-linear-gradient(top,rgba(255,255,255,.5), rgba(255,255,255,0));background-image: -moz-linear-gradient(top,rgba(255,255,255,.5), rgba(255,255,255,0));background-image: -o-linear-gradient(top,rgba(255,255,255,.5), rgba(255,255,255,0));background-image: linear-gradient(top,rgba(255,255,255,.5), rgba(255,255,255,0));background-image: linear-gradient(to bottom,rgba(255,255,255,.5), rgba(255,255,255,0));-ms-filter: "progid:DXImageTransform.Microsoft.gradient(GradientType=0,startColorstr=#50ffffff,endColorstr=#00ffffff)"; /*Filter for IE8 */    filter: progid:DXImageTransform.Microsoft.gradient(GradientType=0,startColorstr=#50ffffff, endColorstr=#00ffffff); /*Filter for older IEs */}

jQuery实现的点击效果：

$(function(){$(".leftnav-item").click(function(e){//e.stopPropagation();var $target = $(e.target);var navindex = $(this).attr("data-index");$(this).find(".leftnav-layer").addClass("cur");$(this).siblings().find(".leftnav-layer").removeClass("cur");$(".gamedata-item").find(".gamedata-layer").removeClass("sel");$("#innervd").css("display","none");if(navindex == 2){$(".gamedata-item").eq(0).find(".gamedata-layer").addClass("sel");$(".gamedata-item").not(':eq(0)').find(".gamedata-layer").removeClass("sel");$(".con").css("display","none");$("#c1").css("display","block");}$(".con-wrapper").css("display","none");$("#con" + navindex).css("display","block");});$(".gamedata-item").click(function(e){e.stopPropagation();//IE阻止冒泡var $target = $(e.target);var liindex = $(this).index() + 1;$(this).find(".gamedata-layer").addClass("sel");$(this).siblings().find(".gamedata-layer").removeClass("sel");$("#innervd").css("display","none");if($target.is("#gamedata-layer" + liindex)){$(".con-wrapper").css("display","none");$("#con2").css("display","block");$(".con").css("display","none");$("#c" + liindex).css("display","block");}});$("#wujiang-link li").mouseover(function(e){var index = $(this).index();$(this).addClass("selected").siblings().removeClass("selected");$("#wujiang-intro li").eq(index).css("display","block");$("#wujiang-intro li").eq(index).siblings().css("display","none");}).eq(0).trigger("mouseover");})

好久没写日志记录了，好像有很多心得，改天继续。