Javascript Form How to - Change what input.value returns








Question

We would like to know how to change what input.value returns.

Answer


<!DOCTYPE html>
<html>
<head>
<script type='text/javascript'>
HTMLInputElement.prototype.MyValue = function() {
    return this.value + this.value;<!--  ww  w. j a va  2 s  .c o m-->
};
window.onload = function() {
    var input = document.getElementById("i");
    console.log(input.MyValue());
};

</script>
</head>
<body>
  <input type="text" value="a" id="i" />
</body>
</html>

The code above is rendered as follows: