### 居中布局 ###
一、水平居中
* 要求:子元素于父元素水平居中且其(子元素与父元素)宽度均可变。
```` javacript
<div class="parent">
<div class="child">Demo</div>
</div>
````
1. inline-block + text-align
.child {
display: inline-block;
}
.parent {
text-align: center;
}
2. table + margin
.child {
display: table;
margin: 0 auto;
}
3. absolute + transform
.parent {
position: relative;
}
.child {
position: absolute;
left: 50%;
transform: translateX(-50%);
}
4. flex + justify-content
.parent {
display: flex;
justify-content: center;
}
5. table-cell + vertical-align
.parent {
display: table-cell;
vertical-align: middle;
}
6. flex + align-items
.parent {
display: flex;
align-items: center;
}
二、水平与垂直居中
* 要求: 子元素于父元素垂直及水平居中且其(子元素与父元素)高度宽度均可变。
<div class="parent">
<div class="child">Demo</div>
</div>
1.inline-block + text-align + table-cell + vertical-align
.parent {
text-align: center;
display: table-cell;
vertical-align: middle;
}
.child {
display: inline-block;
}
2.absolute + transform
.parent {
position: relative;
}
.child {
position: absolute;
left: 50%;
top: 50%;
transform: translate(-50%, -50%);
}
3.flex + justify-content + align-items
.parent {
display: flex;
justify-content: center;
align-items: center;
}
三、多列布局
* 一列定宽,一列自适应
<div class="parent">
<div class="left">
<p>left</p>
</div>
<div class="right">
<p>right</p>
<p>right</p>
</div>
</div>
1.float + margin
.left {
float: left;
width: 100px;
}
.right {
margin-left: 100px
/*间距可再加入 margin-left */
}
2.float + overflow
.left {
float: left;
width: 100px;
}
.right {
overflow: hidden;
}
3.table
.parent {
display: table;
width: 100%;
table-layout: fixed; //table 的显示特性为每列的单元格宽度合一定等与表格宽度。 table-layout: fixed; 可加速渲染,也是设定布局优先。
}
.left {
display: table-cell;
width: 100px;
}
.right {
display: table-cell;
/*宽度为剩余宽度*/
}
4.flex
.parent {
display: flex;
}
.left {
width: 100px;
margin-left: 20px;
}
.right {
flex: 1;
/*等价于*/
/*flex: 1 1 0;*/
}
* 两列定宽,一列自适应
````
<div class="parent">
<div class="left">
<p>left</p>
</div>
<div class="center">
<p>center<p>
</div>
<div class="right">
<p>right</p>
<p>right</p>
</div>
</div>
````
.left, .center {
float: left;
width: 100px;
margin-right: 20px;
}
.right {
overflow: hidden;
/*等价于*/
/*flex: 1 1 0;*/
}
[github地址:https://github.com/Hasyou99/Daily-summary](https://github.com/Hasyou99/Daily-summary)