根据出生日期算出年龄

/*根据出生日期算出年龄*/
function jsGetAge(strBirthday) {
var returnAge;
var strBirthdayArr = strBirthday.split("-");
var birthYear = strBirthdayArr[0];
var birthMonth = strBirthdayArr[1];
var birthDay = strBirthdayArr[2];

d = new Date();
var nowYear = d.getFullYear();
var nowMonth = d.getMonth() + 1; //d.getMonth() 是从0开始的取值0-11
var nowDay = d.getDate();

if (nowYear == birthYear) {
returnAge = 0;//同年 则为0岁
}
else {
var ageDiff = nowYear - birthYear; //年之差
if (ageDiff > 0) {
if (nowMonth == birthMonth) {
var dayDiff = nowDay - birthDay;//日之差
if (dayDiff < 0) {
returnAge = ageDiff - 1;
}
else {
returnAge = ageDiff;
}
}
else {
var monthDiff = nowMonth - birthMonth;//月之差
if (monthDiff < 0) {
returnAge = ageDiff - 1;
}
else {
returnAge = ageDiff;
}
}
}
else {
returnAge = -1;//返回-1 表示出生日期输入错误 晚于今天
}
}

return returnAge;//返回周岁年龄

}

转自：http://blog.csdn.net/a657281084/article/details/50588802