js判断身份证是儿童或者成人

/**   *判断成人和儿童   */   judgeAge : function(idCard) {   var result = "";        var birthDayDate = parseInt(this.getBirthdayFromIdCard(idCard).replace(/-/g,""),10);        var fDate = _STAGE.flightNoInfo.fDate;        var twelveAgeDate = parseInt(((fDate.substr(0,4)*1-12) + fDate.substr(4)).replace(/-/g,""),10);            var twoAgeDate = parseInt(((fDate.substr(0,4)*1-2) + fDate.substr(4)).replace(/-/g,""),10);                 // 儿童机票规定：年龄2-12周岁（个别航空公司不执行此标准），以起飞日期为准if(birthDayDate <= twelveAgeDate){      result = _STAGE.passengerPsgType.ADT;    } else if((birthDayDate <= twoAgeDate ) && (birthDayDate > twelveAgeDate)){      result = _STAGE.passengerPsgType.CHD;    } else {      result = _STAGE.passengerPsgType.ETC;    }return result;   },

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