HTML在两个div标签中间画一条竖线的代码

往常我们画一条横线直接用标签

body{  
    margin-top:100px;  
    margin-left:200px;  
}  
.mainp{  
    width:900px;  
    padding:10px;  
    overflow:hidden; /*关键*/  
    border:1px solid black;  
}  
.leftp{  
    float:left;  
    width:400px;  
    background-color:#CC6633;  
}  
.rightp{  
    float:right;  
    width:400px;  
    background-color:#CC66FF;  
}  
.centerp{  
    float:left;  
    width:50px;  
    border-right: 1px dashed black;  
    padding-bottom:1600px;  /*关键*/  
    margin-bottom:-1600px;  /*关键*/  
}  

  
  
  
  
  
  
  
  
    
  
        






  
        
  
        







  
    
  
  

效果图：

function myfun(){  
  var p1=document.getElementById("content");  
  var p2=document.getElementById("side");  
  var h1=p1.offsetHeight;  
  var h2=p2.offsetHeight;  
    if(h1>h2){  
        p1.style.borderRight="1px dashed #B6AEA3";  
    }else{  
        p2.style.borderLeft="1px dashed #B6AEA3";  
  }  
}