JS 图片大小自动调整 (img)

<script>

function dlutChangeImg(){ 

  var maxwidth = 598;  

var obj = document.getElementById('bbs_font_size');  

var imgs = obj.getElementsByTagName('img');  

  for(var i=0; i<imgs.length; i++){

   var img = imgs[i];

   var width = img.width;

   var height = img.height;

   if(width > maxwidth){

    var p = width/height

        img.width = maxwidth; 

          img.height = parseInt(maxwidth/p);

        img.style.width = maxwidth + "px";

    img.style.height = parseInt(maxwidth/p) + "px";

   }

  }

}

window.onload = function(){   dlutChangeImg(); } </script>