拖动

 $('#tddiv1').mousedown(function (event) {
                 var isMove = true;  
                 var abs_x = event.pageX - $('#tddiv').offset().left;  
                 var abs_y = event.pageY - $('#tddiv').offset().top;  
                 $(window).mousemove(function (event) {  
                     if (isMove) {
                         $('#tddiv').css({'left':event.pageX - abs_x, 'top':event.pageY - abs_y});  
                     }  
                 }).mouseup(function(){  
                     isMove = false;
                     return false;
                 });
                 return false;
 });