JavaScript: Get ISO-8601 numeric representation of the day of the week

Last update on April 24 2023 07:03:38 (UTC/GMT +8 hours)

JavaScript Datetime: Exercise-22 with Solution

Write a JavaScript function to get an ISO-8601 numeric representation of the day of the week (1 (for Monday) to 7 (for Sunday).

Test Data :
dt = new Date();
console.log(ISO_numeric_date(dt));
4
dt = new Date(2015, 10, 1);
console.log(ISO_numeric_date(dt));
7

Sample Solution:-

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript function to get ISO-8601 numeric representation of the day of the week (1 (for Monday) to 7 (for Sunday))</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function ISO_numeric_date(dt)
{
  return (dt.getDay() === 0 ? 7 : dt.getDay()); 
}

dt = new Date();
console.log(ISO_numeric_date(dt));

dt = new Date(2015, 10, 1);
console.log(ISO_numeric_date(dt));

Sample Output:

3
7

Flowchart:

Live Demo:

See the Pen JavaScript - Get ISO-8601 numeric representation of the day of the week-date-ex-22 by w3resource (@w3resource) on CodePen.

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