// 初始化shuju
var init = function() {
var tbl_count = $("#tbl_count tr:gt(0)");
// 吃饭
var meal_text = $("#tbl_count tr:first th:eq(1)").text();
// KTV
var ktv_text = $("#tbl_count tr:first th:eq(2)").text();
// 烧烤
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]; 
      // 判断姓名相同的 
      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 >tbody >tr').length;

$("#myTable").attr('rows').length;

var rowCount = $('table#myTable:last').index() + 1;

//Helper function that gets a count of all the rows in a table body
$.fn.rowCount = function() {
return $('tr',$(this).find('tbody')).length;
};

// USAGE:

var rowCount = $('#productTypesTable').rowCount();

alert(jQuery("#jtkList").find("table").eq(0).find("tr").length);