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flex弹性容器

程煜
程煜原创
2019年11月05日 22:33:06599浏览

一、弹性容器的两种类型

实例

<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>弹性容器的两种类型</title>
		<!-- <link rel="stylesheet" href="css/public.css" /> -->
		<style>
			/* 弹性容器的通用样式 */
			.container{
				border: 2px dashed bisque;
				margin: 12px;
				background-color: #00FFFF;
			}
			/* 弹性元素的通用样式 */
			.item{
				box-sizing: border-box;
				border: 1px solid;
				padding: 20px;
				background-color: #87CEEB;
			}
			.flex{
				/* 将容器设为块级弹性容器 
				不设置span会超出div
				*/
				display: flex;
			}
			.inline-flex{
				display: inline-flex;
			}
			
		</style>
			<!-- 实例弹性盒子制作导航 -->
		<style>
			nav{
				display: flex;
				/* border: 1px solid #ADFF2F; */
			}
			a{
				text-decoration: none;
				background-color: #00FFFF;
				color: black;
				padding: 5px 10px;
				margin: 0 5px;
				border-radius: 5px 5px 0 0;
			}
			/* 当鼠标移动上去或获取焦点或激活时改变背景颜色和字体颜色 */
			a:hover,a:focus,a:active{
				background-color: #ADFF2F;
				color: white;
			}
			
		</style>
	</head>
	<body>
		<h3>块级弹性容器</h3>
		<div class="container flex">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<div class="container flex">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<hr />
		<h3>行内弹性容器</h3>
		<div class="container inline-flex">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<div class="container inline-flex">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		
		<h2>实例弹性盒子制作导航</h2>
		<nav>
			<a href="">首页</a>
			<a href="">w3School</a>
			<a href="">慕课网</a>
			<a href="">php中文网</a>
			<a href="">菜鸟教程</a>
		</nav>
	</body>
</html>

运行实例 »

点击 "运行实例" 按钮查看在线实例

1.png11.png

二、定义弹性容器的主轴方向:弹性元素在主轴上的排列方向

实例

<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>定义弹性容器的主轴方向:弹性元素在主轴上的排列方向</title>
		<!-- <link rel="stylesheet" href="css/public.css" /> -->
		<style>
			/* 弹性容器的通用样式 */
			.container {
				border: 2px dashed bisque;
				margin: 12px;
				background-color: #00FFFF;
			}
			
			/* 弹性元素的通用样式 */
			.item {
				box-sizing: border-box;
				border: 1px solid;
				padding: 20px;
				background-color: #87CEEB;
			}
			
			/*块级弹性盒子/容器*/
			.flex {
				display: flex;
				flex-direction: row;
			}
			
			div {
				width: 450px;
			}
		</style>
		<style>
			.row{
				/* 定义弹性元素在主轴上的排列方向从左到右 */
				flex-direction: row;
			}
			.row-reverse{
				flex-direction: row-reverse;
			}
			.column{
				flex-direction: column;
			}
			.column-reverse{
				flex-direction: column-reverse;
			}
		</style>
		<!-- 创建网站首页 -->
		<style>
			*{
				/* outline与border不同不会影响盒子的大小 */
				/* outline: 1px solid #87CEEB; */
				margin: 8px;
				padding: 8px;
			}
			nav {
				display: flex;
				/* border: 1px solid #ADFF2F; */
			}
			
			a {
				text-decoration: none;
				background-color: #00FFFF;
				color: black;
				padding: 5px 10px;
				margin: 0 5px;
				border-radius: 5px 5px 0 0;
			}
			
			/* 当鼠标移动上去或获取焦点或激活时改变背景颜色和字体颜色 */
			a:hover,
			a:focus,
			a:active {
				background-color: #ADFF2F;
				color: white;
			}
			
			/* 将页面中的所有布局元素转为flex */
			body,nav,main,article{
				display: flex;
			}
			/* 设置元素在主轴上的排列方向 */
			body,article{
				flex-direction: column;
			}
			footer{
				border-top: 1px solid #20B2AA;
			}
			nav{
				padding-bottom: 0;
			}
			img{
				width:350px;
			}
		</style>
	</head>
	<body>
		<h3>1.row:默认从左到右,水平排列</h3>
		<div class="container flex row">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<h3>2.row-reverse:从右到左,水平排列</h3>
		<div class="container flex row-reverse">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<h3>3.column:从上到下,垂直排列</h3>
		<div class="container flex column">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<h3>4.column-reverse:从下到上,垂直排列</h3>
		<div class="container flex column-reverse">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		
		
		<h2>创建网站首页</h2>
		<header>
			<h2>程昱的学习博客</h2>
		</header>
		<nav>
			<a href="">首页</a>
			<a href="">w3School</a>
			<a href="">慕课网</a>
			<a href="">php中文网</a>
			<a href="">菜鸟教程</a>
		</nav>
		<main>
			<article>
				<img src="../../img/1.jpg" />
				<p>PHP即“超文本预处理器”,是一种通用开源脚本语言。PHP是在服务器端执行的脚本语言,与C语言类似,是常用的网站编程语言。PHP独特的语法混合了C、Java、Perl以及 PHP 自创的语法。利于学习,使用广泛,主要适用于Web开发领域</p>
				<button>点击学习</button>
			</article>
			<article>
				<img src="../../img/1.jpg" />
				<p>PHP即“超文本预处理器”,是一种通用开源脚本语言。PHP是在服务器端执行的脚本语言,与C语言类似,是常用的网站编程语言。PHP独特的语法混合了C、Java、Perl以及 PHP 自创的语法。利于学习,使用广泛,主要适用于Web开发领域</p>
				<button>点击学习</button>
			</article>
			<article>
				<img src="../../img/1.jpg" />
				<p>PHP即“超文本预处理器”,是一种通用开源脚本语言。PHP是在服务器端执行的脚本语言,与C语言类似,是常用的网站编程语言。PHP独特的语法混合了C、Java、Perl以及 PHP 自创的语法。利于学习,使用广泛,主要适用于Web开发领域</p>
				<button>点击学习</button>
			</article>
		</main>
		<footer>
			<p>
				 Copyright © 2018 - 2021 
			</p>
		</footer>
	</body>
</html>

运行实例 »

点击 "运行实例" 按钮查看在线实例

例子:创建网站首页

实例

<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>创建网站首页</title>
		<!-- <link rel="stylesheet" href="css/navigation.css" /> -->
		<style>
			nav {
				display: flex;
				/* border: 1px solid #ADFF2F; */
			}
			
			a {
				text-decoration: none;
				background-color: #00FFFF;
				color: black;
				padding: 5px 10px;
				margin: 0 5px;
				border-radius: 5px 5px 0 0;
			}
			
			/* 当鼠标移动上去或获取焦点或激活时改变背景颜色和字体颜色 */
			a:hover,
			a:focus,
			a:active {
				background-color: #ADFF2F;
				color: white;
			}
			
			*{
				/* outline与border不同不会影响盒子的大小 */
				/* outline: 1px solid #87CEEB; */
				margin: 8px;
				padding: 8px;
			}
			/* 将页面中的所有布局元素转为flex */
			body,nav,main,article{
				display: flex;
			}
			/* 设置元素在主轴上的排列方向 */
			body,article{
				flex-direction: column;
			}
			footer{
				border-top: 1px solid #20B2AA;
			}
			nav{
				padding-bottom: 0;
			}
			img{
				width:350px;
			}
		</style>
	</head>
	<body>
		<header>
			<h2>程昱的学习博客</h2>
		</header>
		<nav>
			<a href="">首页</a>
			<a href="">w3School</a>
			<a href="">慕课网</a>
			<a href="">php中文网</a>
			<a href="">菜鸟教程</a>
		</nav>
		<main>
			<article>
				<img src="../../img/1.jpg" />
				<p>PHP即“超文本预处理器”,是一种通用开源脚本语言。PHP是在服务器端执行的脚本语言,与C语言类似,是常用的网站编程语言。PHP独特的语法混合了C、Java、Perl以及 PHP 自创的语法。利于学习,使用广泛,主要适用于Web开发领域</p>
				<button>点击学习</button>
			</article>
			<article>
				<img src="../../img/1.jpg" />
				<p>PHP即“超文本预处理器”,是一种通用开源脚本语言。PHP是在服务器端执行的脚本语言,与C语言类似,是常用的网站编程语言。PHP独特的语法混合了C、Java、Perl以及 PHP 自创的语法。利于学习,使用广泛,主要适用于Web开发领域</p>
				<button>点击学习</button>
			</article>
			<article>
				<img src="../../img/1.jpg" />
				<p>PHP即“超文本预处理器”,是一种通用开源脚本语言。PHP是在服务器端执行的脚本语言,与C语言类似,是常用的网站编程语言。PHP独特的语法混合了C、Java、Perl以及 PHP 自创的语法。利于学习,使用广泛,主要适用于Web开发领域</p>
				<button>点击学习</button>
			</article>
		</main>
		<footer>
			<p>
				 Copyright © 2018 - 2021 
			</p>
		</footer>
	</body>
</html>

运行实例 »

点击 "运行实例" 按钮查看在线实例



2.png22.png

三、弹性元素溢出与创建多行容器

实例

<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>弹性元素溢出与创建多行容器</title>
		<!-- <link rel="stylesheet" href="css/public.css" /> -->
		<style>
			/* 弹性容器的通用样式 */
			.container {
				border: 2px dashed bisque;
				margin: 12px;
				background-color: #00FFFF;
			}
			
			/* 弹性元素的通用样式 */
			.item {
				box-sizing: border-box;
				border: 1px solid;
				padding: 20px;
				background-color: #87CEEB;
			}
			
			/*块级弹性盒子/容器*/
			.flex {
				display: flex;
				flex-direction: row;
			}
			
			div {
				width: 450px;
			}
		</style>
		<style>
			div{
				width: 450px;
			}
			.nowrap{
				flex-direction: row;
				/* 定义弹性元素是否换行 不换行 */
				flex-wrap: nowrap;
				/* 以上两行代码的简写 */
				flex-flow: row nowrap;
			}
			.wrap{
				flex-direction: row;
				flex-wrap: wrap;
				flex-flow: row wrap;
			}
			.wrap-reverse{
				flex-direction: row;
				flex-wrap: wrap-reverse;
				flex-flow: row wrap; 
			}
		</style>
	</head>
	<body>
		<h2>以水平方向进行演示:</h2>
		<h3>1.nowrap:默认不换行,元素自动缩小填充容器</h3>
		<div class="container flex row nowrap">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
			<span class="item">item7</span>
			<span class="item">item8</span>
			<span class="item">item9</span>
			<span class="item">item10</span>
			<span class="item">item11</span>
		</div>
		<hr />
		<h3>2.warp:换行,弹性元素超出的容器边界的换到下一行显示</h3>
		<div class="container flex row wrap">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
			<span class="item">item7</span>
			<span class="item">item8</span>
			<span class="item">item9</span>
			<span class="item">item10</span>
			<span class="item">item11</span>
		</div>
		<h3>3.warp-reverse:换行,弹性元素反转排列</h3>
		<div class="container flex row wrap-reverse">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
			<span class="item">item7</span>
			<span class="item">item8</span>
			<span class="item">item9</span>
			<span class="item">item10</span>
			<span class="item">item11</span>
		</div>
	</body>
</html>

运行实例 »

点击 "运行实例" 按钮查看在线实例

3.png

四、弹性元素在主轴上的分布

实例

<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>弹性元素在主轴上的分布</title>
		<!-- <link rel="stylesheet" href="css/public.css" /> -->
		<style>
			/* 弹性容器的通用样式 */
			.container {
				border: 2px dashed bisque;
				margin: 12px;
				background-color: #00FFFF;
			}
			
			/* 弹性元素的通用样式 */
			.item {
				box-sizing: border-box;
				border: 1px solid;
				padding: 20px;
				background-color: #87CEEB;
			}
			
			/*块级弹性盒子/容器*/
			.flex {
				display: flex;
				flex-direction: row;
			}
			
			div {
				width: 450px;
			}
		</style>
		<style>
			.wrap{
				flex-wrap: wrap;
			}
			.flex-start{
				/* 主轴起点开始排列 */
				justify-content: flex-start;
			}
			.flex-end{
				/* 末尾 */
				justify-content: flex-end;
			}
			.center{
				/* 弹性元素整体居中 */
				justify-content: center;
			}
			/* 首尾元素紧贴起止点,其他元素平分剩余空间 */
			.space-between{
				justify-content: space-between;
			}
			.space-around{
				justify-content: space-around;
			}
			.space-evenly{
				justify-content: space-evenly;
			}
		</style>
		<!-- 导航 -->
		<style>
			nav {
				display: flex;
				/* border: 1px solid #ADFF2F; */
			}
			
			a {
				text-decoration: none;
				background-color: #00FFFF;
				color: black;
				padding: 5px 10px;
				margin: 0 5px;
				border-radius: 5px 5px 0 0;
			}
			
			/* 当鼠标移动上去或获取焦点或激活时改变背景颜色和字体颜色 */
			a:hover,
			a:focus,
			a:active {
				background-color: #ADFF2F;
				color: white;
			}
			
			nav{
				justify-content: flex-start;
			}
			nav{
				justify-content: flex-end;
			}
			nav{
				justify-content: center;
			}
			/* nav{
				justify-content: space-around;
			} */
		</style>
	</head>
	<body>
		<h2>弹性元素在主轴上的分布:</h2>
		<h3>1.flex-start:主轴起点开始排列</h3>
		<p>单行</p>
		<div class="container flex flex-start">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<p>多行</p>
		<div class="container flex wrap flex-start">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
		</div>
		<hr />
		<h3>2.flex-end:主轴终点开始排列</h3>
		<p>单行</p>
		<div class="container flex flex-end">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<p>多行</p>
		<div class="container flex wrap flex-end">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
		</div>
		<hr />
		<h3>3.center:弹性元素整体居中排列</h3>
		<p>单行</p>
		<div class="container flex center">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<p>多行</p>
		<div class="container flex wrap center">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
		</div>
		<hr />
		<h3>4.space-between:首尾元素紧贴起止点,其他元素平分剩余空间</h3>
		<p>单行</p>
		<div class="container flex space-between">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<p>多行</p>
		<div class="container flex wrap space-between">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
		</div>
		<hr />
		<h3>5.space-around:每个元素两边空间相等,相邻元素空间累加</h3>
		<p>单行</p>
		<div class="container flex space-around">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<p>多行</p>
		<div class="container flex wrap space-around">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
		</div>
		<hr />
		<h3>6.space-evenly:每个元素,以及元素到与起止点的空间全部相等</h3>
		<p>单行</p>
		<div class="container flex space-evenly">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<p>多行</p>
		<div class="container flex wrap space-evenly">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
		</div>
		<hr />
		<h2>导航</h2>
		<nav>
		    <a href="">首页</a>
		    <a href="">教学视频</a>
		    <a href="">社区问答</a>
		    <a href="">软件下载</a>
		    <a href="">联系我们</a>
		</nav>
	</body>
</html>

运行实例 »

点击 "运行实例" 按钮查看在线实例

4.png

五、弹性元素在垂直方向上的对齐方式

实例

<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>弹性元素在垂直方向上的对齐方式</title>
		<link rel="stylesheet" href="css/public.css" />
		<style>
			.container{
				width: 450px;
				height: 300px;
			}
			.wrap{
				flex-wrap: wrap;
			}
			/* 单行容器 */
			/* align-items设置单行容器中元素在垂直轴上的排列方式 */
			.stretch{
				align-items: stretch;
			}
			.flex-start{
				align-items: flex-start;
			}
			.flex-end{
				align-items: flex-end;
			}
			.center{
				align-items: center;
			}
			/* 多行容器 */
			/* align-content设置多行容器中元素在垂直轴上的排列方式 */
			.wrap-stretch{
				align-content: stretch;
			}
			.wrap-flex-start{
				align-content: flex-start;
			}
			.wrap-flex-end{
				align-content: flex-end ;
			}
			.wrap-center{
				align-content: center;
			}
			.wrap-space-between{
				align-content: space-between;
			}
			.wrap-space-around{
				align-content: space-around;
			}
			.wrap-space-evenly{
				align-content: space-evenly;
			}
		</style>
	</head>
	<body>
		<h2>弹性元素在垂直轴上分布方式:</h2>
		<h3>1.stretch:默认值,元素高度自动拉伸充满整个容器</h3>
		<p>单行容器</p>
		<div class="container flex stretch">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<p>多行容器</p>
		<div class="container flex wrap wrap-stretch">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
			<span class="item">item7</span>
			<span class="item">item8</span>
			<span class="item">item9</span>
			<span class="item">item10</span>
			<span class="item">item11</span>
			<span class="item">item12</span>
		</div>
		<hr >
		<h3>2.flex-start:元素紧贴容器起点</h3>
		<p>单行容器</p>
		<div class="container flex flex-start">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<p>多行容器</p>
		<div class="container flex wrap wrap-flex-start">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
			<span class="item">item7</span>
			<span class="item">item8</span>
			<span class="item">item9</span>
			<span class="item">item10</span>
			<span class="item">item11</span>
			<span class="item">item12</span>
		</div>
		<hr >
		<h3>3.flex-end:元素紧贴容器终点</h3>
		<p>单行容器</p>
		<div class="container flex flex-end">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<p>多行容器</p>
		<div class="container flex wrap wrap-flex-end">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
			<span class="item">item7</span>
			<span class="item">item8</span>
			<span class="item">item9</span>
			<span class="item">item10</span>
			<span class="item">item11</span>
			<span class="item">item12</span>
		</div>
		<hr >
		<h3>4.center:所有元素作为一个整体在容器垂直方向居中显示</h3>
		<p>单行容器</p>
		<div class="container flex center">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
		</div>
		<p>多行容器</p>
		<div class="container flex wrap wrap-center">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
			<span class="item">item7</span>
			<span class="item">item8</span>
			<span class="item">item9</span>
			<span class="item">item10</span>
			<span class="item">item11</span>
			<span class="item">item12</span>
		</div>
		<hr >
		<h3>5.space-between:垂直方向首尾行紧贴起止点,其它平分剩余空间</h3>
		<p>多行容器</p>
		<div class="container flex wrap wrap-space-between">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
			<span class="item">item7</span>
			<span class="item">item8</span>
			<span class="item">item9</span>
			<span class="item">item10</span>
			<span class="item">item11</span>
			<span class="item">item12</span>
		</div>
		<hr >
		<h3>6.space-around:每个元素两边空间相等,相邻元素空间累加</h3>
		<p>多行容器</p>
		<div class="container flex wrap wrap-space-around">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
			<span class="item">item7</span>
			<span class="item">item8</span>
			<span class="item">item9</span>
			<span class="item">item10</span>
			<span class="item">item11</span>
			<span class="item">item12</span>
		</div>
		<hr >
		<h3>7.space-evenly:每个元素,以及元素到与起止点的空间全部相等</h3>
		<p>多行容器</p>
		<div class="container flex wrap wrap-space-evenly">
			<span class="item">item1</span>
			<span class="item">item2</span>
			<span class="item">item3</span>
			<span class="item">item4</span>
			<span class="item">item5</span>
			<span class="item">item6</span>
			<span class="item">item7</span>
			<span class="item">item8</span>
			<span class="item">item9</span>
			<span class="item">item10</span>
			<span class="item">item11</span>
			<span class="item">item12</span>
		</div>
		<hr >
	</body>
</html>

运行实例 »

点击 "运行实例" 按钮查看在线实例

5.png


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