Update hidden input field value with another input field value?

Question

I am trying to update one hidden input field with another visible input field using javascript...

but my code doesn't work for some reason!!

This is my javascript:

<script language="javascript">
    function process1() {
        document.getElementById("sum_total").value = (document.getElementById("my-item-price").value);
    }
</script>

And This Is My form code:

<form><input name="A1" type="text" class="A1" id="A1"/></form>

<form><input type="hidden" id="A2" name="A2" value="process1() "/></form>

Update

<script language="javascript"> 
    function process1() { 
        document.getElementById("sum_total").value = (document.getElementById("my-item-price").value); 
    } 
</script>

Answer 1

The code you have is bad. You haven´t got ids you are looking for in javascript.

Try this:

 <script language="javascript">
 function process1(showed) {
    document.getElementById("A2").value = showed.value;
}
</script>

<form><input name="A1" type="text" class="A1" onChange="process1(this)"/></form>

<form><input type="hidden" id="A2" name="A2" value="5" /></form>