CSS全屏布局的5种方式

思路一: float

【1】float + calc　　通过calc()函数计算出.middle元素的高度，并设置子元素高度为100%

<style>body,p{margin: 0;}body,html,.parent{height: 100%;}.middle{
overflow: hidden;
height: calc(100% - 100px);}.left{
float: left;
width: 100px;
margin-right: 20px;
height: 100%;}.right{
overflow: auto;
height: 100%;}.right-in{
height: 1000px;}.top,.bottom{height:50px;}</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>

【2】float + absolute + (fix)　　通过增加结构来提高兼容性，.middle元素设置100%的高度，.top和.bottom设置absolute覆盖在.middle上

<style>body,p{margin: 0;}body,html,.parent{height: 100%;}.top,.bottom{
position: absolute;
height:50px;
left: 0;
right: 0;}.top{top: 0;}.bottom{bottom: 0;}.middleWrap{
height: 100%;
overflow: hidden;}.middle{
overflow: hidden;
height: 100%;
margin: 50px 0;}.left{
float: left;
width: 100px;
margin-right: 20px;
height: 100%;}.right{
overflow: auto;
height: 100%;}.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="middleWrap">
<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>
<div class="bottom" style="background-color: lightgreen;">
<p>bottom</p>
</div>        </div>

思路二: inline-block

【1】inline-block + calc

<style>body,p{margin: 0;}body,html,.parent{height: 100%;}.middle{
height: calc(100% - 100px);
font-size: 0;}.left,.right{
display: inline-block;
vertical-align: top;
font-size: 16px;}.left{
width: 100px;
margin-right: 20px;
height: 100%;}.right{
width: calc(100% - 120px);
height: 100%;
overflow: auto;}.right-in{
height: 1000px;}.top,.bottom{height: 50px;}</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>

【2】inline-block + absolute + (fix)

<style>body,p{margin: 0;}body,html,.parent{height: 100%;}.top,.bottom{
position: absolute;
left: 0;
right: 0;
height: 50px;}.top{top: 0;}.bottom{bottom: 0;}.middleWrap{
height: 100%;
font-size: 0;
overflow: hidden;}.middle{
position: relative;
height: 100%;
margin: 50px 0;
overflow: hidden;}.left,.rightWrap{
display: inline-block;
vertical-align: top;
font-size: 16px;}.left{
position: absolute;
width: 100px;
margin-right: 20px;
height: 100%;}.rightWrap{
width: 100%;
height: 100%;}.right{
height: 100%;
margin-left: 120px;
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="middleWrap">
<div class="middle" style="background-color: pink;">
<div class="left" style="background-color: orange;">
<p>left</p>
</div>
<div class="rightWrap">
<div class="right" style="background-color: lightsalmon;">
<div class="right-in">
<p>right</p>
</div>
</div>
</div>
</div>
</div>
<div class="bottom" style="background-color: lightgreen;">
<p>bottom</p>
</div>        </div>

思路三: table

　　水平方向子元素的间距可以用border实现。所有浏览器都不支持给table-cell元素设置overflow属性。firefox和IE11浏览器不支持给table-cell元素的设置100%高度的子元素设置overflow属性

<style>body,p{margin: 0;}body,html,.parent{height: 100%;}.top,.bottom{
position: absolute;
width: 100%;
height: 50px;}.bottom{bottom: 0;}.middleWrap{
height: 100%;
overflow: hidden;}.middle{
width: 100%;
height: 100%;
display: table;
margin: 50px 0;
table-layout: fixed;}.left{
display: table-cell;
width: 120px;
border-right: 20px solid lightgray;}.rightWrap{
display: table-cell;
height: 100%;}.right{
height: 100%;
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="middleWrap">
<div class="middle" style="background-color: pink;">
<div class="left" style="background-color: orange;">
<p>left</p>
</div>
<div class="rightWrap">
<div class="right" style="background-color: lightsalmon;">
<div class="right-in">
<p>right</p>
</div>
</div>
</div>
</div>
</div>
<div class="bottom" style="background-color: lightgreen;">
<p>bottom</p>
</div>        </div>

思路四: absolute

<style>body,p{margin: 0;}body,html,.parent{height: 100%;}.top,.middle,.bottom{
position: absolute;
left: 0;
right: 0;}.top{
top: 0;
height: 50px;}.bottom{
bottom: 0;
height: 50px;}.middle{
top: 50px;
bottom: 50px;}.left,.right{
position: absolute;
top: 0;
bottom: 0;}.left{
width:100px;}.right{
left: 120px;
right: 0;
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>

思路五: flex

　　flex常用于小范围的布局，使用全屏布局时会因为性能问题，出现卡顿现象。如果要使用全屏自适应布局，则只有flex才能达到效果

<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>