Correct Answer:
C
JavaScript form validation typically occurs after the form is submitted but before the form data is sent to the server. This allows the client-side script to check the input data and prevent the form from being submitted if the data is invalid.
Client-Side Validation:
Before Form Submission: JavaScript validates the form fields after the user attempts to submit the form.
Prevent Default Submission: If the validation fails, JavaScript can prevent the form from being submitted and display appropriate error messages.
Usage Example:
document.getElementById('myForm').addEventListener('submit', function(event) {
var isValid = true;
// Perform validation checks
if (!isValid) {
event.preventDefault(); // Prevent form submission
alert('Please correct the errors.');
}
});
This example prevents form submission if the validation fails.
MDN Web Docs on Form Validation
W3C HTML Specification on Form Submission
