formData-example.js

// Yoink: https://www.javascripttutorial.net/web-apis/javascript-formdata/

const btn = document.querySelector('#submit-btn-id');
const form = document.querySelector('#my-form-id');

btn.addEventListener('click', (e) => {
    // prevent the form from submitting
    // or uncomment the debugger statment below for a breakpoint  
    //   if needing to also send the data for testing 
    e.preventDefault();

    // show the form values
    const formData = new FormData(form);
    const values = [...formData.entries()];
    console.log(values);
  
    // comment out the preventDefault and uncomment below to sue breakpoints instead
    // debugger;
});