JS根据生日算年龄的方法

function parseDate(str){ if(str.match(/^/d{4}[/-///s+]/d{1,2}[/-///s+]/d{1,2}$/)){  return new Date(str.replace(/[/-///s+]/i,'/')); } else if(str.match(/^/d{8}$/)){  return new Date(str.substring(0,4)+'/'+str.substring(4,6)+'/'+str.substring(6)); } else{  return ('时间转换发生错误！'); }}function GetAgeByBrithday(birthday){ var age=-1; var today=new Date(); var todayYear=today.getFullYear(); var todayMonth=today.getMonth()+1; var todayDay=today.getDate(); var birthday=parseDate(birthday); if(parseDate(birthday)!='时间转换发生错误！') { birthdayYear=birthday.getFullYear(); birthdayMonth=birthday.getMonth(); birthdayDay=birthday.getDate(); if(todayYear-birthdayYear<0) {  alert("出生日期选择错误!"); } else {  if(todayMonth*1-birthdayMonth*1<0)  {    age = (todayYear*1-birthdayYear*1)-1;  }  else  {    if(todayDay-birthdayDay>=0)    {//alert(thisDay+'-'+brithd+"_ddd");      age = (todayYear*1-birthdayYear*1);    }    else    {      age = (todayYear*1-birthdayYear*1)-1;    }  } } return age*1; } else { return -1; }}