///自动调整图片大小
<script language=javascript>
function propersize(obj,width,height)
{
var width1=obj.width;
var height1=obj.height;           
var width2=width;           
var height2=height;           
var h=height1/height2;
var w=width1/width2;

  if(h>w)
  {
   obj.height=height2;         
   obj.width=width1*height2/height1;          
  }
  else
  {
   obj.width=width2;          
   obj.height=height1*width2/width1;         
  }
}
</script>