JAVASCRIPT
Validate Date Format (YYYY-MM-DD) with Regex
Ensure date inputs conform to 'YYYY-MM-DD' format using a JavaScript regex pattern, providing basic validation for form fields and data entry.
function validateYYYYMMDD(dateString) {
const dateRegex = new RegExp("^\\d{4}-(0[1-9]|1[0-2])-(0[1-9]|[12]\\d|3[01])$");
return dateRegex.test(dateString);
}
// Example usage:
console.log(validateYYYYMMDD("2023-10-26")); // true
console.log(validateYYYYMMDD("1999-02-29")); // true (Does not validate for leap years, just format)
console.log(validateYYYYMMDD("2023-13-01")); // false (invalid month)
console.log(validateYYYYMMDD("2023-10-32")); // false (invalid day)
How it works: This JavaScript function validates if a string adheres to the YYYY-MM-DD date format using a regular expression. The regex checks for four digits for the year, a valid month (01-12), and a valid day (01-31). While it ensures the format, it does not perform advanced date validation like checking for leap years or days in specific months, which would require additional logic.