.td_back_color {   background-color: red; } .td_center {   text-align: center;   font-weight:bold; } 

CSS：

<table id="tbl_count">       <caption>2013春節聚會收支統計</caption>       <tr>         <th>姓名</th>         <th>吃飯</th>         <th>KTV</th>         <th>燒烤</th>         <th>支出</th>         <th>應付</th>       </tr>       <tr>         <th>周競成</th>         <td></td>         <td></td>         <td></td>         <td></td>         <td></td>       </tr>       ......     </table> 

var data = [ {       picture : "http://ww1.sinaimg.cn/mw690/51baa38egw1dzl6l2hjchj.jpg",       name : "周競成",       leftTime : "二月五號",       phone : "186****2296",       qq : "",       workedIn : "浙江 杭州",       cost : 200,       project : "吃飯，KTV，燒烤"     }, ........ // 初始化shuju     var init = function() {       var tbl_count = $("#tbl_count tr:gt(0)");       // 吃飯       var meal_text = $("#tbl_count tr:first th:eq(1)").text();       // KTV       var ktv_text = $("#tbl_count tr:first th:eq(2)").text();       // 燒烤       var bbq_text = $("#tbl_count tr:first th:eq(3)").text();        $.each(tbl_count, function(i,v){         var tr_info = tbl_count.eq(i);         for (var i = 0; i < data.length; i++) {           var data_info = data[i];           // 判斷姓名相同的           if(data_info.name == tr_info.find("th:first").text()){             if(data_info.project.indexOf(meal_text) != -1){               tr_info.find("td:eq(0)").addClass("td_back_color");             }             if(data_info.project.indexOf(ktv_text) != -1){               tr_info.find("td:eq(1)").addClass("td_back_color");             }             if(data_info.project.indexOf(bbq_text) != -1){               tr_info.find("td:eq(2)").addClass("td_back_color");             }             tr_info.find("td:eq(3)").addClass("td_center").text("￥"+data_info.cost);           }         }       });     }; 

var rowCount = $('#myTable tr').length; var rowCount = $('#myTable >tbody >tr').length; $("#myTable").attr('rows').length; var rowCount = $('table#myTable:last').index() + 1; //Helper function that gets a count of all the rows <TR> in a table body <TBODY> $.fn.rowCount = function() {   return $('tr', $(this).find('tbody')).length; };  // USAGE:  var rowCount = $('#productTypesTable').rowCount(); alert(jQuery("#jtkList").find("table").eq(0).find("tr").length);