anchor.diff:          // 通过判断滚动条的top位置与可视网页之和与整个网页的高度是否相等来决定是否加载内容；
           let he = scrollTop + clientHeight;
   
  -        if (JSON.parse(answersHasNextPage) && he == htmlHeight) {
  -            if ($('#default-sort').hasClass('custom-current')) {
  -                showMore(questionId, parseInt(answersPageNum) + 1, '/default-more-answers');
  -            } else {
  -                showMore(questionId, parseInt(answersPageNum) + 1, '/time-more-answers');
  +        // 加载缓冲区为 50px
  +        if (JSON.parse(answersHasNextPage) && he >= htmlHeight - 50) {
  +            if(lock) {
  +                lock = false;
  +                if ($('#default-sort').hasClass('custom-current')) {
  +                    showMore(questionId, parseInt(answersPageNum) + 1, '/default-more-answers');
  +                } else {
  +                    showMore(questionId, parseInt(answersPageNum) + 1, '/time-more-answers');
  +                }
               }
           }
       });
  
positive.code:             },
              success: function(dataRec) {
                  $('#show_more_btn').addClass('hide');
  
                  console.log(dataRec);
  
                  let data = dataRec['list'];
                  let page = dataRec['page'];
  
negative.code: <input type="hidden" id="answersHasNextPage" value="${page.hasNextPage}">
  
  <script type="text/javascript">
      // 防止重复加载
      let lock = true;
      $(window).scroll(function () {
  
          let answersPageNum = $('#answersPageNum').val();
  