鼠标控制图片缩放的代码

鼠标控制图片缩放的代码(IE下面可以使用)
<SCRIPT language=JavaScript type=text/JavaScript>
      var isdrag = false;      
function img_zoom(e, o) //图片鼠标滚轮缩放 {    
      var zoom = parseInt(o.style.zoom, 10) || 100;    
      zoom += event.wheelDelta / 12;       
   if (zoom > 0)         
     o.style.zoom = zoom + '%';      
    return false;    
  }      
function mouseover() {    
      div1.border = "1";      
    div1.style.cursor = "nw-resize";   
   }     
function mouseout() {      
    div1.border = "0";    
      }   
function mousemove() {   
             if (isdrag) {    
                       div1.style.width = event.clientX; 
                       //div1.style.height=event.clientY;     
                   }    
  }   
  function mousedown() {      
     div1.setCapture();      
     isdrag = true;    
     div1.onmousemove = mousemove;  
  }     
  function mouseup() {  
     div1.releaseCapture();
    isdrag = false;         
     //event.returnValue=false;   
  }  
</SCRIPT>
<IMG onmouseover="mouseover()" onmouseout="mouseout()"
onmouseup="mouseup()" onmousedown="mousedown()" id="div1"
onmousewheel="return img_zoom(event,this)" alt="鼠标的滚轮控制图片自动缩放"
src="http://www.java2000.net/images/company/www.java2000.net.gif"
onload="javascript:if(this.width>screen.width-500)this.width=screen.width-500">