ie6，ie7的haslayout属性是个让人头疼的问题。在做导航条的时候，一般会用到ul li结构，大多数时候我们是把li设置为浮动，让其并排显示在同一行。还有一种方法就是设置li为display:inline;这样可以达到同样的效果，但是问题是inline元素的特性：默认无法设置宽度，高度，以及上下margin，（关于padding，情况有点特殊，在ie6，7中 inline元素是无法设置上下padding的，但是在标准浏览器里面是可以设置上下padding的）。
鉴于inline元素的这种特性，如果我们不浮动并且想让li显示在一行，而且可以设置高度，宽度以及上下margin，上下padding等属性，应该怎么办呢？你一定会想到一个属性display:inline-block;对！”inline- block”就是干这个事的，让一个元素既不换行又具有block元素的特性。不过有点小问题.
在IE6、IE7中不识别display:inline-block属性，加不加display:inline-block;对于它们完全没有任何影响。那么让我们来想办法解决这个问题，这就涉及到ie6，7中的haslayout属性了。ie6，7中的inline元素有个特殊的情况，就是触发了ie的hasLayout属性以后就拥有了layout。此时inline元素的表现和标准浏览器里面的inline-block元素基本相同。
可以看到在ie6，7中inline元素span已经表现得和一个display:inline-block元素一摸一样了，但是在标准浏览器中span仍然是行内元素（宽高以及上下margin都无效）。
如果声明了不正确DTD，导致ie6在quirks 模式下解析，那么ie6会自动触发inline元素的haslayout，不过这里只讨论正常情况下的解析，所以加了个zoom:1来触发haslayout;zoom的值设置为除了auto外的任何值都会触发haslayout，之所以经常用zoom:1;是因为zoom这个属性本身是ie的缩放属性，设置为其他值会导致元素在ie下变形，设置为1既是保持原形不缩放。
li <span style="font-family:宋体,微软雅黑,Verdana,Helvetica">{</span>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica">display:inline-block; /* firefox等标准浏览器识别*/ </span>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica">*display:inline; /* 只有ie6和ie7识别*/zoom:1; /* 触发ie6和ie7下的haslayout */ </span>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica">width:80px; </span>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica">height:20px; </span>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica">margin:10px; </span>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica">padding:10px; </span>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica">text-align:center; </span>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica">background:#cfc; </span>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica">}</span>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"> 让标准浏览器识别display:inline-block;让ie6，7识别display:inline;来覆盖上面的display:inline-block;（我为什么要说”覆盖”？）。然后通过zoom:1;来触发haslayout让inline元素在ie中表现得和inline-block元素一样。</span>
</span>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html"><html xmlns=”http://www.w3.org/1999/xhtml”> </pre><pre name="code" class="html"><head> </pre><pre name="code" class="html"><meta http-equiv=”Content-Type” content=”text/html; charset=utf-8″ /> </pre><pre name="code" class="html"><title>display-block</title> </pre><pre name="code" class="html"><style> </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">ul {</pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">background:#ccc;</pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">padding:0;</pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">margin:0;</pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">list-style:none;</pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">} </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">li {</pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">display:inline-block; </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">*display:inline; </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">zoom:1; </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">width:80px; </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">height:20px; </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">margin:10px; </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">padding:10px; </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">text-align:center; </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html">background:#cfc;</pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html"> } </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html"></style> </pre><pre name="code" class="html"></head> </pre><pre name="code" class="html"><body> </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html"><ul> </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html"><li>测试</li> </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html"><li>测试</li> </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html"><li>测试</li> </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html"><li>测试</li> </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html"></ul> </pre>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px"></span></span><pre name="code" class="html"></body> </pre><pre name="code" class="html"></html></pre><span style="color:rgb(17,17,17); font-family:宋体,微软雅黑,Verdana,Helvetica; font-size:14px; line-height:25px">可以看到，现在在各浏览器里面的显示已经一致了。li元素都显示在同一行。</span>
<span style="font-family:宋体,微软雅黑,Verdana,Helvetica"><a target="_blank" href="http://www.poluoluo.com/jzxy/201206/167493.html">http://www.poluoluo.com/jzxy/201206/167493.html</a>
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