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JavaScript: Calculate age

JavaScript Datetime: Exercise-18 with Solution

Write a JavaScript program to calculate age.

Test Data:
console.log(calculate_age(new Date(1982, 11, 4)));
35
console.log(calculate_age(new Date(1962, 1, 1)));
56

Sample Solution:-

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript program to calculate age</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function calculate_age(dob) { 
    var diff_ms = Date.now() - dob.getTime();
    var age_dt = new Date(diff_ms); 
  
    return Math.abs(age_dt.getUTCFullYear() - 1970);
}

console.log(calculate_age(new Date(1982, 11, 4)));

console.log(calculate_age(new Date(1962, 1, 1)));

Sample Output:

35
56

Flowchart:

Flowchart: JavaScript- Calculate age

Live Demo:

See the Pen JavaScript - Calculate age-date-ex-18 by w3resource (@w3resource) on CodePen.


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Next: Write a JavaScript function to get the day of the month, 2 digits with leading zeros.

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JavaScript: Tips of the Day

Removes elements in an array until the passed function returns true. Returns the removed elements.

Example:

const tips_remove = (arr, func) => {
  for (const [i, val] of arr.entries()) if (func(val)) return arr.slice(0, i);
  return arr;
};

console.log(tips_remove([1, 2, 3, 4, 5, 6], n => n >= 5));

Output:

[1, 2, 3, 4]