An OnChange Input Event

This JavaScript program shows how to handle an onchange event in an input element.

OnChangeInput.html

<!DOCTYPE html>
<html>
  <head>
    <script>
function fnChangedValue(sValue) {
  document.getElementById("idNewValue").innerHTML = "You changed the value to " + sValue;
}
    </script>
  </head>
  <body>
    <p>Enter New Text:</p>
    <!-- This event only happens when the value is acually changed. -->
    <input type="text" name="txt" value="Initial" onchange="fnChangedValue(this.value)">
    <p id="idNewValue"></p>
  </body>
</html>

Core JavaScript

An OnChange Input Event

OnChangeInput.html

Output