Check if a Date is Valid with JavaScript
An HTML form requires users to select the year, month and date in separate dropdown fields without using a date picker. The developer needs to ensure that the values selected by the users form a valid date. For instance, an input like 2 (Month), 30 (Date) should be rejected.
function isValidDate() {
var day = Number(document.getElementById('day').value),
month = Number(document.getElementById('month').value),
year = Number(document.getElementById('year').value);
var date = new Date();
date.setFullYear(year, month - 1, day);
// month - 1 since the month index is 0-based (0 = January)
if (date.getFullYear() == year && date.getMonth() == month + 1 && date.getDate() == day) return true;
return false;
}
Amit Agarwal
Google Developer Expert, Google Cloud Champion
Amit Agarwal is a Google Developer Expert in Google Workspace and Google Apps Script. He holds an engineering degree in Computer Science (I.I.T.) and is the first professional blogger in India.
Amit has developed several popular Google add-ons including Mail Merge for Gmail and Document Studio. Read more on Lifehacker and YourStory
