input on change 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 html textbox on change

<!-- 
	You can use any of the following:
	onkeydown, onkeyup or onchange
 -->

<input type="text" onkeydown="keydownFunction()" 
onkeyup="keyupFunction()" onchange="changeFunction()">

Example 3: 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 4: javascript input value change

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