var oDiv=document.getElementById('div1');

     var oParent=document.getElementById('parent');

     var oDiv2=document.getElementById('div2');

     oDiv.onmousedown=function(ev){

         var oEvent=ev||event;

         var disX=oEvent.clientX-oDiv.offsetLeft;

         document.onmousemove=function(ev){

             var oEvent=ev||event;

             var l=oEvent.clientX-disX;document.title=l;

             if(l<0){

                 l=0;

             }else if(l>oParent.offsetWidth-oDiv.offsetWidth){

                 l=oParent.offsetWidth-oDiv.offsetWidth;

             }

             oDiv.style.left=l+'px';

             var scale=l/(oParent.offsetWidth-oDiv.offsetWidth);

             oDiv2.style.width=scale*300+'px';

             oDiv2.style.height=30+'px';

         }

         document.onmouseup=function(){

             document.onmousemove=null;

             document.onmouseup=null;

         }

     }