第三章Div水平居中

1.div居中

text-align:center可以让元素里面的文字内容居中，但并不能让div居中。要让div水平居中必须设置div宽度，外边距设置为margin:0 auto

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="AlignCenter.aspx.cs" Inherits="布局.AlignCenter" %>

<!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 runat="server">
    <title>最简单的页面</title>
    <style type ="text/css" >
        body
        {
            text-align :center;
        }
        
        .poetry_box
        {
            background-color:#E8E8E8;
            width:250px;
            margin:0 auto;
        }
    </style>
</head>
<body>
    <form id="form1" runat="server">
    <div class ="poetry_box" >
        <h1 >春晓</h1>
        <address >唐代&middot;孟浩然</address>
        <p>春眠不觉晓，处处闻啼鸟。</p>
        <p>夜来风雨声，花落知多少。</p>
    </div>
    </form>
</body>
</html>

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2.div居右

让div居右显示有两种方式：浮动和定位

浮动：

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="AlignCenter.aspx.cs" Inherits="布局.AlignCenter" %>

<!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 runat="server">
    <title>最简单的页面</title>
    <style type ="text/css" >
        
        .poetry_box
        {
            float:right;
            background-color:#E8E8E8;
            width:250px;
        }
    </style>
</head>
<body>
    <form id="form1" runat="server">
    <div class ="poetry_box" >
        <h1 >春晓</h1>
        <address >唐代&middot;孟浩然</address>
        <p>春眠不觉晓，处处闻啼鸟。</p>
        <p>夜来风雨声，花落知多少。</p>
    </div>
    </form>
</body>
</html>

View Code

定位：

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="AlignCenter.aspx.cs" Inherits="布局.AlignCenter" %>

<!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 runat="server">
    <title>最简单的页面</title>
    <style type ="text/css" >
        
        .poetry_box
        {
            position:absolute ;
            right:0;
            background-color:#E8E8E8;
            width:250px;
        }
    </style>
</head>
<body>
    <form id="form1" runat="server">
    <div class ="poetry_box" >
        <h1 >春晓</h1>
        <address >唐代&middot;孟浩然</address>
        <p>春眠不觉晓，处处闻啼鸟。</p>
        <p>夜来风雨声，花落知多少。</p>
    </div>
    </form>
</body>
</html>

View Code