如果给出格式为YYYYMMDD的出生日期，如何以年计算年龄?是否可以使用Date()函数?
我正在寻找一个比我现在使用的更好的解决方案:
Var dob = '19800810'; var年=数字(dob.)substr (0, 4)); var月=数字(dob.)Substr (4, 2)) - 1; var day =数字(dob.)2) substr(6日); var today = new Date(); var age = today.getFullYear() -年份; if (today.getMonth() < month || (today.getMonth() == month && today.getDate() < day)) { 年龄——; ｝ 警报(年龄);
当前回答
替代解决方案，因为为什么不呢:
function calculateAgeInYears (date) {
var now = new Date();
var current_year = now.getFullYear();
var year_diff = current_year - date.getFullYear();
var birthday_this_year = new Date(current_year, date.getMonth(), date.getDate());
var has_had_birthday_this_year = (now >= birthday_this_year);
return has_had_birthday_this_year
? year_diff
: year_diff - 1;
}
其他回答
我认为可以简单地像这样:
function age(dateString){
let birth = new Date(dateString);
let now = new Date();
let beforeBirth = ((() => {birth.setDate(now.getDate());birth.setMonth(now.getMonth()); return birth.getTime()})() < birth.getTime()) ? 0 : 1;
return now.getFullYear() - birth.getFullYear() - beforeBirth;
}
age('09/20/1981');
//35
也适用于时间戳
age(403501000000)
//34
使用momentjs "fromNow"方法， 这允许您使用格式化的日期，例如:03/15/1968
var dob = document.getElementByID（“dob”）; var age = moment（dob.value）.fromNow（true）.replace（“ years”， “”）;
//fromNow(true) =>后缀“ago”不显示 //但是我们还是要去掉“years”;
作为原型版本
String.prototype.getAge = function() {
return moment(this.valueOf()).fromNow(true).replace(" years", "");
}
let dt = dob;
let age = '';
let bY = Number(moment(dt).format('YYYY'));
let bM = Number(moment(dt).format('MM'));
let bD = Number(moment(dt).format('DD'));
let tY = Number(moment().format('YYYY'));
let tM = Number(moment().format('MM'));
let tD = Number(moment().format('DD'));
age += (tY - bY) + ' Y ';
if (tM < bM) {
age += (tM - bM + 12) + ' M ';
tY = tY - 1;
} else {
age += (tM - bM) + ' M '
}
if (tD < bD) {
age += (tD - bD + 30) + ' D ';
tM = tM - 1;
} else {
age += (tD - bD) + ' D '
}
//AGE MONTH DAYS
console.log(age);
function change(){
setTimeout(function(){
var dateObj = new Date();
var month = dateObj.getUTCMonth() + 1; //months from 1-12
var day = dateObj.getUTCDate();
var year = dateObj.getUTCFullYear();
var newdate = year + "/" + month + "/" + day;
var entered_birthdate = document.getElementById('birth_dates').value;
var birthdate = new Date(entered_birthdate);
var birth_year = birthdate.getUTCFullYear();
var birth_month = birthdate.getUTCMonth() + 1;
var birth_date = birthdate.getUTCDate();
var age_year = (year-birth_year);
var age_month = (month-birth_month);
var age_date = ((day-birth_date) < 0)?(31+(day-birth_date)):(day-birth_date);
var test = (birth_year>year)?true:((age_year===0)?((month<birth_month)?true:((month===birth_month)?(day < birth_date):false)):false) ;
if (test === true || (document.getElementById("birth_dates").value=== "")){
document.getElementById("ages").innerHTML = "";
} else{
var age = (age_year > 1)?age_year:( ((age_year=== 1 )&&(age_month >= 0))?age_year:((age_month < 0)?(age_month+12):((age_month > 1)?age_month: ( ((age_month===1) && (day>birth_date) ) ? age_month:age_date) ) ));
var ages = ((age===age_date)&&(age!==age_month)&&(age!==age_year))?(age_date+"days"):((((age===age_month+12)||(age===age_month)&&(age!==age_year))?(age+"months"):age_year+"years"));
document.getElementById("ages").innerHTML = ages;
}
}, 30);
};
替代解决方案，因为为什么不呢:
function calculateAgeInYears (date) {
var now = new Date();
var current_year = now.getFullYear();
var year_diff = current_year - date.getFullYear();
var birthday_this_year = new Date(current_year, date.getMonth(), date.getDate());
var has_had_birthday_this_year = (now >= birthday_this_year);
return has_had_birthday_this_year
? year_diff
: year_diff - 1;
}
