ユーザーの誕生日から数日、数か月、数年続くことを示したいと思います。
ここから抜粋した私のコードは次のとおりです: JavaScript で年齢を計算する
方法は次のとおりです。
ユーザーの誕生日: 2010/04/29
結果は次のようになります: 2 歳 4 か月 5 日。
function getAge(dateString) {
var today = new Date();
var birthDate = new Date(dateString);
var age = today.getFullYear() - birthDate.getFullYear();
var m = today.getMonth() - birthDate.getMonth();
if (m < 0 || (m === 0 && today.getDate() < birthDate.getDate())) {
age--;
}
return age;
}
alert(getAge('2010/04/29'));
function getAge(dateString) {
var now = new Date();
var today = new Date(now.getYear(),now.getMonth(),now.getDate());
var yearNow = now.getYear();
var monthNow = now.getMonth();
var dateNow = now.getDate();
var dob = new Date(dateString.substring(6,10),
dateString.substring(0,2)-1,
dateString.substring(3,5)
);
var yearDob = dob.getYear();
var monthDob = dob.getMonth();
var dateDob = dob.getDate();
var age = {};
var ageString = "";
var yearString = "";
var monthString = "";
var dayString = "";
yearAge = yearNow - yearDob;
if (monthNow >= monthDob)
var monthAge = monthNow - monthDob;
else {
yearAge--;
var monthAge = 12 + monthNow -monthDob;
}
if (dateNow >= dateDob)
var dateAge = dateNow - dateDob;
else {
monthAge--;
var dateAge = 31 + dateNow - dateDob;
if (monthAge < 0) {
monthAge = 11;
yearAge--;
}
}
age = {
years: yearAge,
months: monthAge,
days: dateAge
};
if ( age.years > 1 ) yearString = " years";
else yearString = " year";
if ( age.months> 1 ) monthString = " months";
else monthString = " month";
if ( age.days > 1 ) dayString = " days";
else dayString = " day";
if ( (age.years > 0) && (age.months > 0) && (age.days > 0) )
ageString = age.years + yearString + ", " + age.months + monthString + ", and " + age.days + dayString + " old.";
else if ( (age.years == 0) && (age.months == 0) && (age.days > 0) )
ageString = "Only " + age.days + dayString + " old!";
else if ( (age.years > 0) && (age.months == 0) && (age.days == 0) )
ageString = age.years + yearString + " old. Happy Birthday!!";
else if ( (age.years > 0) && (age.months > 0) && (age.days == 0) )
ageString = age.years + yearString + " and " + age.months + monthString + " old.";
else if ( (age.years == 0) && (age.months > 0) && (age.days > 0) )
ageString = age.months + monthString + " and " + age.days + dayString + " old.";
else if ( (age.years > 0) && (age.months == 0) && (age.days > 0) )
ageString = age.years + yearString + " and " + age.days + dayString + " old.";
else if ( (age.years == 0) && (age.months > 0) && (age.days == 0) )
ageString = age.months + monthString + " old.";
else ageString = "Oops! Could not calculate age!";
return ageString;
}
alert(getAge('09/09/1989'));
format によって制限されたくないmm/dd/yyyy場合は、次のものを置き換えることができます。
var dob = new Date(dateString.substring(6,10),
dateString.substring(0,2)-1,
dateString.substring(3,5)
);
と：
var dob = new Date(dateString);
これにより、use 2012/09/30 を使用しても正しい答えを得ることができます。
年、月、日で年齢を計算します。「1952/09/28」、「1952 年 9 月 29 日」、「09/28/1952」などの有効な日付文字列形式で日付を入力します。
生年月日と年齢を計算する日付の 2 つの引数を取ります。今日の日付の 2 番目の引数を省略できます。age の年、月、日のプロパティを持つオブジェクトを返します。
1 年は 365.2425 日という太陽年の値を使用します。
@parambirthDate 生年月日。@param ageAtDate 年齢を計算する日付。今日の日付はありません。@returns {{年: 数値、月: 数値、日: 数値}}
function getAge(birthDate, ageAtDate) {
var daysInMonth = 30.436875; // Days in a month on average.
var dob = new Date(birthDate);
var aad;
if (!ageAtDate) aad = new Date();
else aad = new Date(ageAtDate);
var yearAad = aad.getFullYear();
var yearDob = dob.getFullYear();
var years = yearAad - yearDob; // Get age in years.
dob.setFullYear(yearAad); // Set birthday for this year.
var aadMillis = aad.getTime();
var dobMillis = dob.getTime();
if (aadMillis < dobMillis) {
--years;
dob.setFullYear(yearAad - 1); // Set to previous year's birthday
dobMillis = dob.getTime();
}
var days = (aadMillis - dobMillis) / 86400000;
var monthsDec = days / daysInMonth; // Months with remainder.
var months = Math.floor(monthsDec); // Remove fraction from month.
days = Math.floor(daysInMonth * (monthsDec - months));
return {years: years, months: months, days: days};
}
受け入れられた解決策に問題があったので (そこにある私のコメントを参照)、生年月日を 1 だけ増やしても日数に「ジャンプ」がないことを保証する独自のバージョンをここに提示します。
このコードは、DateInterval2 つの日付の差を表すためのより一般的なクラスを定義します。関数getAgeは、そのクラスに基づくシン実装になります。
class DateInterval {
constructor(start, end) { // two Date instances
if (start > end) [start, end] = [end, start]; // swap
this.days = end.getDate() - start.getDate();
this.months = end.getMonth() - start.getMonth();
this.years = end.getFullYear() - start.getFullYear();
if (this.days < 0) {
// Add the number of days that are left in the month of the start date
this.days += (new Date(start.getFullYear(), start.getMonth() + 1, 0)).getDate();
this.months--;
}
if (this.months < 0) {
this.months += 12;
this.years--;
}
}
toString() {
const arr = ["years", "months", "days"].map(p =>
this[p] && (this[p] + " " + p.slice(0, this[p] > 1 ? undefined : -1))
).filter(Boolean);
if (!arr.length) return "0 days";
const last = arr.pop();
return arr.length ? [arr.join(", "), last].join(" and ") : last;
}
}
function getAge(dateString) {
let today = new Date();
today.setHours(0,0,0,0);
let dob = new Date(dateString);
dob.setHours(0,0,0,0);
return new DateInterval(dob, today) + " old.";
}
// Demo: increment the date of birth by 1 at each test:
let d = new Date(2000, 1, 1);
setInterval(() => {
const s = d.toJSON().slice(0,10);
console.log("Someone born on " + s + " is now " + getAge(s));
d = new Date(d.getFullYear(), d.getMonth(), d.getDate() + 1);
}, 300); function CalculateAge(DobString) {
$("#age").val(getAge(DobString));
}
function getAge(dateString) {
var now = new Date('2019/01/20');
var today = new Date(now.getYear(), now.getMonth(), now.getDate());
var yearNow = now.getYear();
var monthNow = now.getMonth();
var dateNow = now.getDate();
var dob = new Date(dateString.substring(6, 10),
dateString.substring(3, 5) - 1,
dateString.substring(0, 2)
);
var yearDob = dob.getYear();
var monthDob = dob.getMonth();
var dateDob = dob.getDate();
var age = {};
var ageString = "";
var yearString = "";
var monthString = "";
var dayString = "";
yearAge = yearNow - yearDob;
if (monthNow >= monthDob)
var monthAge = monthNow - monthDob;
else {
yearAge--;
var monthAge = 12 + monthNow - monthDob;
}
if (dateNow >= dateDob)
var dateAge = dateNow - dateDob;
else {
monthAge--;
var dateAge = 31 + dateNow - dateDob;
if (monthAge < 0) {
monthAge = 11;
yearAge--;
}
}
age = {
years: yearAge,
months: monthAge,
days: dateAge
};
if (age.years > 1) yearString = " years";
else yearString = " year";
if (age.months > 1) monthString = " months";
else monthString = " month";
if (age.days > 1) dayString = " days";
else dayString = " day";
if ((age.years > 0) && (age.months > 0) && (age.days > 0))
ageString = age.years + yearString + ", " + age.months + monthString + " " + age.days + dayString + " ";
else if ((age.years == 0) && (age.months == 0) && (age.days > 0))
ageString = " " + age.days + dayString + " ";
else if ((age.years > 0) && (age.months == 0) && (age.days == 0))
ageString = age.years + yearString + " ";
else if ((age.years > 0) && (age.months > 0) && (age.days == 0))
ageString = age.years + yearString + " " + age.months + monthString + " ";
else if ((age.years == 0) && (age.months > 0) && (age.days > 0))
ageString = age.months + monthString + " " + age.days + dayString + " ";
else if ((age.years > 0) && (age.months == 0) && (age.days > 0))
ageString = age.years + yearString + " " + age.days + dayString + " ";
else if ((age.years == 0) && (age.months > 0) && (age.days == 0))
ageString = age.months + monthString + " ";
else ageString = "Oops! Could not calculate age!";
return ageString;
}