css-tips/div-center-middle-align.html at master · vanzheng/css-tips · GitHub

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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">

<head>
    <meta http-equiv="content-type" content="text/html; charset=UTF-8">
    <title>div水平垂直居中</title>
    <style type="text/css">
    .wrapper1 {
        width: 300px;
        height: 300px;
        border: 1px solid #000;
        background-color: #DDF879;
        display: table;
        vertical-align: middle;
    }
    .inner1 {
        display: table-cell;
        vertical-align: middle;
    }
    .content1 {
        margin: 0 10px;
        padding: 5px;
        height: 50px;
        border: 1px solid #ccc;
    }
    .code-section {
        background: #ddd;
    }
    .wrapper2 {
        width: 300px;
        height: 300px;
        border: 1px solid #000;
        background-color: #DDF879;
        position: relative;
        text-align: center;
    }
    #content2 {
        position: absolute;
        top: 50%;
        margin-top: -25px;
        height: 50px;
    }
    .content2 {
        margin: 10px;
        padding: 5px;
        border: 1px solid #ccc;
        display: block;
    }
    .wrapper3 {
        width: 300px;
        height: 300px;
        border: 1px solid #000;
        background-color: #DDF879;
        text-align: center;
    }
    #float3 {
        float: left;
        height: 50%;
    }
    #content3 {
        position: relative;
        top: 50%;
        margin-top: -25px;
        height: 50px;
    }
    .content3 {
        margin: 10px;
        padding: 5px;
        border: 1px solid #ccc;
        display: block;
    }
    .wrapper4 {
        position: relative;
        width: 300px;
        height: 300px;
        border: 1px solid #000;
        background-color: #DDF879;
    }
    .inner4 {
        position: absolute;
        top: 0;
        right: 0;
        left: 0;
        bottom: 0;
        margin: auto;
        width: 90%;
        height: 50px;
        border: 1px solid #ccc;
    }
    </style>
</head>

<body>
    <h2>div水平垂直居中</h2>
    <h3>方法一</h3>
    <p>这个方法把div 的显示方式设置为表格, IE8以上浏览器支持</p>
    <p class="code-section">
        <code>.wrapper{display: table;}</code>
        <br />
        <code>.inner{display: table-cell; vertical-align:middle;}</code>
    </p>
    <div class="wrapper1">
        <div class="inner1">
            <div class="content1">
                <p>aaaaaaaaaaaaaaaaa</p>
            </div>

        </div>
    </div>
    <h3>方法二</h3>
    <p>方法使用绝对定位的 div，把它的 top 设置为 50％，top margin 设置为负的 content 高度。这意味着对象必须在 CSS 中指定固定的高度。</p>
    <p class="code-section">
        <code>.content2{position: absolute; top: 50%; margin-top: -25px; height: 50px;}</code>
    </p>
    <div class="wrapper2">
        <div class="content2" id="content2">
            <p>aaaaaaaaaaaaaaaaaaaaaaaaaaaaa</p>
        </div>
    </div>
    <h3>方法三</h3>
    <p>在 content 元素外插入一个 div。设置此 div height:50%; margin-bottom:-contentheight;。 content 清除浮动，并显示在中间。</p>
    <p class="code-section">
        <code>#float3  {float:left; height:50%; margin-bottom:-25px;}</code>
        <br />
        <code>#content3  {clear:both; height:50px; position:relative;}</code>
    </p>
    <div class="wrapper3">
        <div id="float3"></div>
        <div class="content3" id="content3">
            <p>aaaaaaaaaaaaaaaaaaaaaaaaaaaaa</p>
        </div>
    </div>
    <h3>方法四</h3>
    <p>这个方法使用了一个 position:absolute，有固定宽度和高度的 div。这个 div 被设置为 top:0; bottom:0;。但是因为它有固定高度，其实并不能和上下都间距为 0，因此 margin:auto; 会使它居中。使用 margin:auto;使块级元素垂直居中是很简单的。</p>
    <pre class="code-section">
        <code>
            .inner4{
                position: absolute;
                top: 0;
                right: 0;
                left: 0;
                bottom: 0;
                margin: auto;
                width: 90%;
                height: 50px;
                border: 1px solid #ccc;
            }
        </code>
    </pre>
    <div class="wrapper4">
        <div class="inner4">
            <p>aaaaaaaaaaaaaaaaa</p>
        </div>
    </div>
</body>

</html>