循环嵌套

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<style type="text/css">
   #show{
    width:150px;
 height: 280px;
 margin:0 auto;
 background:#2c2c2c;
 color:red;
 text-align:center;
   }
</style>
<title>循环</title>
    <script type="text/javascript" >
    var str="";
    for (i=1;i<10;i++ )
    {
      for(j=0;j<i;j++)
   {
    if(j==0||j==i-1||i==9)
      {str+="*";}
      else{str+="&nbsp;"}
   }
   str+="</br>"
    }
    document.write("<div id='show'>"+str+"</div>");

 
 </script>
</head>
<body>
 
</body>
</html>

posted @ 2014-01-14 17:35  birdlow  阅读(134)  评论(0)    收藏  举报