Question

How do I pass a JS boolean to hidden CFINPUT field when a user has edited text in a specific input text field?

Answer 1

Let say this is your field

<input type="text" id="textbox1" value="abc def" name="somename1" onchange="passToHiddenField()" />

And this is your hidden input field

<input type="hidden" id="hidden1" name="somename2" value="" />

Then add the script function

<script>
function passToHiddenField(){
     document.getElementById('hidden1').value = 1; //do whatever you want in this function.
}
</script>