determine value of hidden field from user input

[JBWebWorks]

I have a form and a user types in an asking price for an item.

I want to have a hidden field determine a value of .75 times the value of the asking price field.

the form will input the information into a MYSQL database.

How do i arrive at the hidden field value based on the user input into the asking price field?

Thanks for your help,

Jim Balthrop

[Lon_Winters]

If you're going to use the hidden field as the field that inserts the resulting value into the database, then this has to be done before the page is submitted. It may work with javascript and the onChange event of the input field, perform the calculation and set the value of the hidden field.

Or you could modify the insert code and woulnd't need the hidden field. Redefine the form field variable with the calcuation before the actual insert, and use the input field as the one that send the value to the database,

[JBWebWorks]

thanks for your response,

I needed both inputs to be inserted into the database. I tried different coding for the insert command but could not get it to work (but it probably could be done that way).

I found a way to do it with jQuery.

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"...

<script language="javascript" type="text/javascript">

function calculateHiddenValue () {

      var newvalue = $(this).val() * .75;

      $('#hiddenField2auctionopen').val(newvalue);

}

$(document).ready(function() {

      $('#v_ask_price').keyup(calculateHiddenValue);

});

</script>

[Lon_Winters]

I did wonder if you needed to insert both values.

Very creative solution - Thank you for sharing it!