change event listener code example

Example 1: js select on change value

document.getElementById('my-select').addEventListener('change', function() {
  console.log('You selected: ', this.value);
});

Example 2: js addeventlistener change select

<input id="test" type="text" value="Sélectionnez-moi !" />
<script>
  var elem = document.getElementById('test');
  elem.addEventListener('select', function() {
    alert('La sélection a changé !');
  }, false);
</script>

Example 3: javascript input onchange get value

var element = document.getElementById("myInput");
element.onchange = function() {
  console.log(element.value);
}

Example 4: javascript input value change

function updateInput(ish){
    document.getElementById("fieldname").value = ish;
}

Example 5: handling event changes

<p>This page turns violet when you hold the V key.</p>
<script>
  window.addEventListener("keydown", event => {
    if (event.key == "v") {
      document.body.style.background = "violet";
    }
  });
  window.addEventListener("keyup", event => {
    if (event.key == "v") {
      document.body.style.background = "";
    }
  });
</script>