css实现常用的两栏三栏布局

1、两栏

<div class="wrapper">
   <div class="half left">left box
       <p>自适应</p>
   </div>
   <div class="half right">right box 固定</div>
</div>

1.1、左侧宽度固定，右侧自适应

方式一、float+margin

.wrapper{
    width: 100%;
    overflow: auto;    //清浮动
}
.left{
     float: left;
     width: 200px;
     background-color: #5cb85c;
}
.right{
    margin-left: 230px;
    background-color: #66afe9;
}

方式二、float+overflow

.wrapper{
    width: 100%;
    overflow: auto;    //清浮动,或overflow:hidden
}
.left{
     float: left;
     width: 200px;
     margin-left: 30px;
     background-color: #5cb85c;
}
.right{
    overflow: hidden;    //或overflow: auto
    background-color: #66afe9;
}

方式三、float+position

.wrapper{
    position: relative;
    width: 100%;
    overflow: auto;    //清浮动,或overflow:hidden
}
.left{
     float: left;
     width: 200px;
     background-color: #5cb85c;
}
.right{
    position: absolute;
    left: 230px;
    right: 0;
    background-color: #66afe9;
}

方式四、flex

.wrapper{
    display: flex;
    flex-direction: row;
    width: 100%;
}
.left{
     flex: 0 0 auto;
     width: 200px;
     margin-right: 30px;
     background-color: #5cb85c;
}
.right{
    flex: 1;
    background-color: #66afe9;
}

2、三栏

两边固定中间自适应

方式一、float+margin

<div class="wrapper">
    <div class="left">left box
        <p>固定</p>
    </div>
    <div class="right">right box
        <h4>ssss</h4>
        <h5>ddddd</h5>
    </div>
    <div class="middle">中间自适应</div>
</div>

//css
.wrapper{
  width: %;
  overflow: auto;
}

.wrapper .left{
  float: left;
  width: 200px;
  background-color: #5cb85c;
}
.wrapper .right{
  float: right;
  width: 100px;
  background-color: #66afe9;
}
.wrapper .middle{
  margin:  110px  230px;
  background-color: #A3AEFF;
}

方式二、position+margin (这种方式的父元素高度取决于中间部分的高度，当两侧高度大于中间高度时，则出现高度塌陷，除非指定父元素的高度，当两侧高度小于中间部分时，可以使用。)

.wrapper{
  position: relative;
  width: 100%;
}

.wrapper .left{
  position: absolute;
  left: 0;
  width: 200px;
  background-color: #5cb85c;
}
.wrapper .right{
  position: absolute;
  right: 0;
  width: 100px;
  background-color: #66afe9;
}
.wrapper .middle{
  margin: 0 110px 0 230px;
  background-color: #A3AEFF;
}

方式三、flex

<div class="wrapper">
        <div class="left">left box
            <p>固定</p>
        </div>
        <div class="middle">中间自适应</div>
        <div class="right">right box
            <h4>ssss</h4>
            <h5>ddddd</h5>
        </div>
</div>

.wrapper{
   display: flex;
   flex-direction: row;
   width: %;
   .left{
        width: 200px;
        background-color: #5cb85c;
   }
   .right{
         width: 100px;
         background-color: #66afe9;
   }
   .middle{
       flex: ;
       margin:  10px  30px;
       background-color: #A3AEFF;
    }
}