//js等比缩略图片函数
 <!-- 
function resizeimage(imgd,fitwidth,fitheight){
     var image=new image();
     image.src=imgd.src;
	 image.width=imgd.width;
	 image.height=imgd.height;
     if(image.width>0 && image.height>0){
         if(image.width/image.height>= fitwidth/fitheight){
             if(image.width>fitwidth){
                 imgd.width=fitwidth;
                 imgd.height=(image.height*fitwidth)/image.width;
             }else{
                 imgd.width=image.width; 
                imgd.height=image.height;
             }
         } else{
             if(image.height>fitheight){
                 imgd.height=fitheight;
                 imgd.width=(image.width*fitheight)/image.height;
             }else{
                 imgd.width=image.width; 
                imgd.height=image.height;
             } 
        }
     }    
	 //imgd.parentnode.style.top = parseint((fitheight-imgd.height)/2)+"px";
 }
  function resizeposition(imgd){
     var image=new image();
     image.src=imgd.src;
	 imgd.style.position = "absolute";
	 imgd.style.left = "50%";
	 imgd.style.top = "50%";
	 imgd.style.marginleft = -parseint(imgd.width/2)+'px';
	 imgd.style.margintop = -parseint(imgd.height/2)+'px';
 }
 //-->