Check out example codes for "javascript get form data". It will help you in understanding the concepts better.

Code Example 1

<html>
    <form id="myForm">
        <input type="text" name="email" value="[email protected]">
    </form>
    <p id='text'></p>

    <script>
        window.setInterval(()=>{
            var myForm = document.getElementById('myForm');
            var text = document.getElementById('text');

            text.innerText = myForm.elements['email'].value;
        }, 1);
    </script>
</html>

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