jqery 选中不了某个元素的解决方案

demo 计算时间差:

<script>
  $(document).ready(function(){
          console.log('12312');
      $("body").on('change','#f83964',function(){
    start = $(this).val();
              console.log('2323');
    $("body").on('change','#f15612',function(){
        over = $(this).val();
        overtime = new Date(over);
        startime = new Date(start);
        dif = overtime - startime;
                  days = parseInt(dif/1000/60/60/24) + 1;
                $("#f77748").val(days);
    });

    });

  });
</script>

//demo2

$("body").on("click",".layui-disabled",function(){

layer.msg('系统文件夹,无法选中',{time:500});

});