javascript - 从年龄获取出生日期的逻辑以年月日表示

Question

我正在制作一个 react 组件，它具有出生日期输入和年龄输入，以年、月和日为单位输入。

因此，如果输入了年龄，我想获取该人的出生日期。

例如， 年龄为年 = 24，月 = 1，天 = 15所以出生日期应该是 18-04-1993..

这是我到目前为止所做的...但是逻辑在 if (nowDay <= AgeDay) block 处被破坏了..

const now = new Date();
const nowDay = now.getDate();
const nowMonth = now.getMonth() + 1;
const nowYear = now.getFullYear();
const ageYear = ReactDOM.findDOMNode(this.yearInput).value;
const ageMonth = ReactDOM.findDOMNode(this.monthInput).value;
const ageDay = ReactDOM.findDOMNode(this.daysInput).value;
let dobYear = nowYear - ageYear;
let dobMonth = nowMonth - ageMonth;
let dobDay = nowDay - ageDay;
if (dobMonth <= 0) {
  dobYear --;
  dobMonth = (12 + dobMonth);
}
if (ageMonth > 12) {
  dobYear = dobYear + Math.floor(dobMonth / 12);
  console.log('ASIJASOIJAS', dobYear); // eslint-disable-line
  dobMonth = ageMonth % 12;
}
if (nowDay <= ageDay) {
  dobMonth -= Math.floor(ageDay / 30);
  dobDay = ageDay % 30;
  if (dobMonth < 0) {
    dobYear = dobYear - (dobMonth % 12) - 1;
    dobMonth = 12 - (dobMonth % 12);
    dobDay ++;
  }
}
const age = {
  days: ageDay,
  months: ageMonth,
  years: ageYear,
};
const month = dobMonth < 10 ? `0${dobMonth}` : dobMonth;
const day = dobDay < 10 ? `0${dobDay}` : dobDay;
dateOfBirth = `${dobYear}-${month}-${day}`;

提前致谢。

Answer 1

如果您不想使用momentjs正如上面评论中所建议的，像这样的简单函数可能会达到目的。请注意，它返回一个 Date 对象，因此您必须将其格式化为您想要的任何字符串格式。

const getBirthDateFromAge = (ageYears, ageMonths, ageDays) => {
  const date = new Date();
  date.setFullYear(date.getFullYear() - ageYears);
  date.setMonth(date.getMonth() - ageMonths);
  date.setDate(date.getDate() - ageDays);
  return date;
};

console.log(getBirthDateFromAge(10, 9, 4));