1. How many days are before birthday:
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<script> // Given the month and date of the birthday, calculate how many days have passed the birthday function getDaysToBirthday (month, day) {
var nowTime = new Date ();
var thisYear = nowTime.getFullYear ();
// this year's birthday var birthday = new Date (thisYear, month-1 , day);// This year's birthday has passed, then calculate the number of days until next birthday if (birthday <
nowTime) {
birthday.setFullYear(nowTime.getFullYear() + 1);
}
var timeDec = birthday - nowTime;
var days = timeDec / (24 * 60 * 60 * 1000);
return Math.ceil(days);
}
getDaysToBirthday(11, 2);
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2. Calculate the age based on the date of birth:
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<script> // Whether the leap year function isLeap (year) {
return (year% 4 === 0 && year% 100! == 0) || (year% 400 === 0 );
} // Calculate the age based on the date of birth function getAge (year, month, day) {
// Get the current date var nowTime = new Date ();var age = nowTime.getFullYear ()-year; // roughly calculate the age
// If the birthday is February 29 and this year is not a leap year, the birthday of this year is calculated on the 28th
if (month === 2 && day === 29 &&! IsLeap (nowTime.getFullYear ())) {
day = 28 ;
}
// Get this year ’s birthday
var nowBirthday = new Date (nowTime.getFullYear (), month-1 , day);
console.log (nowBirthday, nowTime);
if (nowBirthday> nowTime) { // if this year ’s If you have n’t had a birthday, you will lose one year
age-- ;
}
return age;
}
console.log (getAge ( 2000, 2, 29 ));
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