how to use input radio without button in javascript code example

Example 1: get radio button value javascript

document.querySelector('input[name="rate"]:checked').value;

Example 2: getting value from radio button javascript

var elements = document.getElementsByName('radioButton');
    var checkedButton;
    console.log(elements);
    elements.forEach(e => {
        if (e.checked) {
            //if radio button is checked, set sort style
            checkedButton = e.value;
        }
    });