Question

I have create an eshop.
I have enter an input field for ‘quantity’ and When i click on a submit button the products will be added in my basket. But if i press the submit button with empty the quantity field it will redirect me to an empty page.

So I want to attach an event to the form submission so that nothing is done if the quantity field is empty.

New in javascript, Thanks in advance!

Answer 1

document.getElementById("formId").onsubmit = function () {
    if (!document.getElementById("myField").value) {
        return false;
    }
}

This will capture the submit action of your form and verify that a given field is not empty. Returning false interrupts the form submission. This can also be done by passing an event parameter to the function and then using e.preventDefault().