Automatically load the next page of data when the js page scrolls to the bottom

A piece of js code that automatically loads more data when scrolling to the bottom of the page. It requires the support of jquery.js and jquey.tmpl.js

var Data = {
      PageCount: 1,
      PageSize: 30,
      IsCompleted: false,
      init: function(rows) { //初始化，载入第一页数据
        $(".list-item").detach();
        Data.IsCompleted = false;
        Data.load(1, rows);
      },
      setPage: function() { //数据载入成功，设置下一页索引
        var $page = $("#PageIndex");
        var index = parseInt($page.val()) + 1;
        $page.val(index);
      },
      scroll: function(page, rows) { //滚动到底部加载数据
        if (Data.IsCompleted) {
          return false;
        }
        var top = $(window).scrollTop();
        var win = $(window).height();
        var doc = $(document).height();
        if ((top + win) >= doc) {
          Data.load(page, rows);
        }
      },
      load: function(page, rows) { //载入数据方法
        $("#PageIndex").val(page);
        var chkSubject = $("#chkSubject").prop("checked"); 
        var chkContent = $("#chkContent").prop("checked");
        var logical = $('input:radio[name="rbtnLogical"]:checked').val();
	    var selectedTypeId = $("#hfdselectedId").val();

        var $msg = $('.load-btn');
        $msg.removeClass('load-more').text('正在载入数据...');
        $.ajax({
          url: "?pageindex=" + page + 
          "&pagesize=" + rows + 
          "&keywords=" + encodeURI($("#txtKeyWords").val()) + 
          "&chkSubject=" + chkSubject + 
          "&chkContent=" + chkContent + 
          "&logical=" + logical + 
          "&typeid=" + selectedTypeId + 
          "&t=" + (new Date().getTime()),
          type: "POST",
          success: function(json) {
            Data.PageCount = json.PageCount;
            var data = json.List;
            if (data != null && data.length > 0) {
              Data.append(data);
              if (Data.PageCount == page) {
                Data.IsCompleted = true;
                $msg.removeClass('load-more').text('已加载全部数据！');
                return true;
              }
              Data.setPage();
              $msg.addClass('load-more').text('查看更多');
              return true;
            }
            $msg.removeClass('load-more').text('已加载全部数据！');
            return false;
          },
          error: function (XMLHttpRequest, textStatus, errorThrown)  {
            $msg.removeClass('load-more').text('数据加载失败！点击重试。');
            alert(errorThrown + ":" + textStatus);
          }
        });
        return false;
      },
      append: function(json) { //构造html，并填充
        var $container = $('.table');
        $.each(json, function(i) {
          var html = $("#list-item-template").tmpl(json[i]);
          html.appendTo($container);
        });
      }
    };
	
    var $page = $("#PageIndex"); //页索引
        
    //初始化
    Data.init(Data.PageSize);
        
    //滚动加载
    $(window).scroll(function () {
      Data.scroll($page.val(), Data.PageSize);
    });
        
    //手动加载
    $(".load-btn").bind("click", function () {
      Data.load($page.val(), Data.PageSize);
    });
    //查询
    $("#btnSearch").bind("click", function () {
      Data.init(Data.PageSize);
    });