php+ajax实现带进度条的大数据排队导出思路以及源码

            retrun_var = excel_export_ajax(index, num, processnum, tabletype);

            if(typeof(retrun_var)=='undefined'){           
                  iii++;
                  excel_export2(num, processnum);
                  if(iii>100){
                        return false;
                  }
            }else if(retrun_var=='success'){
                  return false;
            }
            return false;
      }else{
            //setTimeout(excel_export2(num, processnum),3000);
            //setInterval(_excel_export2(num, processnum),3000);
            setTimeout(_excel_export2(num, processnum),3000);
      }
}
function _excel_export2(num, processnum){
       return function(){
             excel_export2(num, processnum);
       }
}
/* 执行导出 */
function excel_export(num, processnum){
    var retrun_var = 'ss';
    for (var i in count_arr){
        num = count_arr[i];
        tabletype = i;
        index = 1;
        retrun_var = excel_export_ajax(index, num, processnum, tabletype);

        if(typeof(retrun_var)=='undefined'){
            //alert('xxxx');
            setTimeout(function(){exit;},5000);
        }
        if (retrun_var == 'success')
        {
            return false;
        }