为什么我的两列在IE7中不能正确对齐？

Question

我通过书籍和网站自学CSS。我已经创建了一个简单的站点，它有一个居中的框，后面跟着两列，它在Firefox3和Safari3中显示得很好，但在IE7中就不行了。我的右列保持在右边，但被向下推，这样它就从左列结束的地方开始。我看过很多关于IE黑客的博客，但我不知道应该应用哪个，或者应该在我的代码中添加它。任何建议都将不胜感激！

这是我的CSS：

#wrapper {
position:relative;
width:900px;
margin-right:auto;
margin-left:auto;
}

#centerbox {
background-color:#FFFFFF;
width:870px;
margin-left:auto;
margin-right:auto;
padding:10px 15px 10px 15px;
margin-bottom:30px;
text-align:left;
border:8px solid #E0BB24;
}

#leftcolumn {
float:left;
margin-left:10px;
width:410px;
padding:0px 10px 10px 10px;
color:#FFFFFF;
}

#rightcolumn {
width:395px;
margin-left:480px;
margin-right:10px;
padding:0px 15px 10px 10px;
background-color:#FFFFFF;
border:1px solid #26A9E0;
}

这是我的HTML：

<div id="centerbox" class="clear">
<h1>The physician's creed: &quot;First, do no harm&quot;</h1>
<h3>Politicians, policymakers, and public officials should take the same oauth</h3>
<p>Text</p>
</div>

<div id="leftcolumn">
<h2><img src="images/accept.png" alt="Putting Patients First" align="left"> </img>Putting Patients First</h2>
<p class="spaceafter"><a href="betterway.html">Read more about our idea of a better way to reform health care by putting patients first &raquo;</a></p>

<h2><img src="images/reject.png" alt="Principles for reform" align="left"></img>Principles for reform</h2>
<p class="spaceafter">Tell politicians in Washington you will follow these <a href="donoharm.html">principles</a> in judging any health reform proposal:</p>
<ul>
    <li>No new government-run health insurance plan</li>
    <li>No one-size government-dictated package of health benefits</li>
    <li>No new jobs-killing mandates on employers</li>
    <li>No requirement on individuals to buy this expensive coverage</li>
    <li>No federal institution that controls private health insurance</li>
    <li>No government intrusion into our medical privacy</li>
    <li>No federal government control over the practice of medicine through a federal health board, comparative effectiveness review, and other government intrusions into doctor-patient medical decision-making</li>
</ul>
<p><a href="donoharm.html">Read more &raquo;</a></p>
</div>

<div id="rightcolumn">
<h2><img src="images/signpetition.png" alt="Sign the petition" align="left">    </img>Sign the petition</h2>
<p>Dear Policymaker: I stand with millions of Americans who implore you to follow the Do No Harm principles &mdash; and do NOT destroy America's health care system!</p>
<iframe height="920px" width="400px" name="zoho-Do_No_Harm_Petition" frameborder="0" scrolling="auto" src="http://creator.zoho.com/galeninstitute/do-no-harm-petition/form-embed/Do_No_Harm_Petition/reAUnSRw7O3sfWaOssaxgN91NbXFRYWUEQ8AZ5v803j2bVG4OHpFAXkvuUuqDVX9zxfg5YMSfMD9TTeqds1OE1kbYQqSSmYbFh6Z/"></iframe>
</div>

Answer 1

我认为您错过了# right列上的浮动

#rightcolumn {
     float: right;
}

您还可以从#rightcolumn中删除这些值。

margin-left:480px;
margin-right:10px; 

Answer 2

这就是我对三列div所做的(左、中、右都是div)

这三个像素都是310px，中间是10px (总共950px)，你可以根据你的尺寸进行调整。

诀窍在于中间的div，它基本上占据了整个“row”的空间，但有足够的填充来清除位于中间div顶部的“浮动”的左右div的内容。

#left
{
    float: left;
    width: 310px;
}

#middle
{
    padding: 0px 320px 5px 320px;
}

#right
{
    float: right;
    width: 310px;
}