CSS的flex在布局中的用法

元素居中

【1】伸缩容器上使用主轴对齐justify-content和侧轴对齐align-items

<style>.parent{
    display: flex;
    justify-content: center;
    align-items: center;}</style>
<div class="parent"  style="background-color: lightgrey; height: 100px; width: 200px;">
    <div class="in" style="background-color: lightblue;">DEMO</div>      </div>

【2】在伸缩项目上使用margin:auto

<style>.parent{
    display: flex;}.in{
    margin: auto;}</style>
<div class="parent"  style="background-color: lightgrey;height: 100px;width: 200px;">
    <div class="in" style="background-color: lightblue;">DEMO</div>      </div>

两端对齐

<style>.parent{
   display: flex;    
   justify-content:space-between
   }
</style>
<div class="parent"  style="background-color: lightgrey;height: 100px;width: 200px;">
    <div class="in" style="background-color: lightblue;">DEMO</div>
    <div class="in" style="background-color: lightgreen;">DEMO</div>
    <div class="in" style="background-color: lightcyan;">DEMO</div>    
    <div class="in" style="background-color: lightseagreen;">DEMO</div>     
 </div>

底端对齐

<style>.parent{
    display: flex;
    align-items: flex-end;
    }
</style>
<div class="parent"  style="background-color: lightgrey;height: 100px;width: 200px;">
    <div class="in" style="background-color: lightblue; height:20px;">DEMO</div>
    <div class="in" style="background-color: lightgreen; height:30px;">DEMO</div>
    <div class="in" style="background-color: lightcyan; height:40px;">DEMO</div>
    <div class="in" style="background-color: lightseagreen; height:50px;">DEMO</div>      
</div>

输入框按钮

<style>.inputBox{
    display: flex;
    width: 250px;}.inputBox-ipt{
    flex: 1;}
</style>
<div class="inputBox">
  <input class="inputBox-ipt">
  <button class="inputBox-btn">按钮</button>
</div>

等分布局

<style>body,p{margin: 0;}.parent{
    display: flex;}.child{
    flex:1;
    height: 100px;}.child + .child{
    margin-left: 20px;}
</style>
<div class="parent" style="background-color: lightgrey;">
    <div class="child" style="background-color: lightblue;">1</div>
    <div class="child" style="background-color: lightgreen;">2</div>
    <div class="child" style="background-color: lightsalmon;">3</div>
    <div class="child" style="background-color: pink;">4</div>                
</div>

多列自适应布局

<style>p{margin: 0;}.parent{display: flex;}.left,.center{margin-right: 20px;}.right{flex: 1;}</style>
<div class="parent" style="background-color: lightgrey;">
    <div class="left" style="background-color: lightblue;">
        <p>left</p>
        <p>left</p>
    </div>            
    <div class="center" style="background-color: pink;">
        <p>center</p>
        <p>center</p>
    </div>            
    <div class="right"  style="background-color: lightgreen;">
        <p>right</p>
        <p>right</p>
    </div>                    
</div>

悬挂布局

<style>        
     .box{
    display: flex;
    background-color: lightgrey;
    width: 300px;}.left{
    margin-right: 20px;
    background-color: lightblue;
    height: 30px;}.main{
    flex:1;}
 </style>
<div class="box">
    <div class="left">左侧悬挂</div>
    <div class="main">主要内容主要内容主要内容主要内容主要内容主要内容主要内容主要内容主要内容主要内容主要内容主要内容主要内容</div>    
</div>

全屏布局

<style>body,p{margin: 0;}body,html,.parent{height: 100%;}.parent{
    display: flex;
    flex-direction: column;}.top,.bottom{
    height: 50px;}.middle{
    display: flex;
    flex: 1;}.left{
    width: 100px;
    margin-right: 20px;}.right{
    flex: 1;
    overflow: auto;}.right-in{
    height: 1000px;}</style>
<div class="parent" id="parent" style="background-color: lightgrey;">
    <div class="top" style="background-color: lightblue;">
        <p>top</p>
    </div> 
    <div class="middle" style="background-color: pink;">
        <div class="left" style="background-color: orange;">
            <p>left</p>
        </div>     
        <div class="right" style="background-color: lightsalmon;">
            <div class="right-in">
                <p>right</p>
            </div>            
        </div>                    
    </div>              
    <div class="bottom" style="background-color: lightgreen;">
        <p>bottom</p>
    </div>        
</div>

以上就是CSS弹性盒模型flex在布局中的使用方法的详细内容，更多请关注亿速云其它相关文章！