using the selected value of a drop down before form submission

Question

i am using a dropdown in php which asks for user_category before creating the user. Upon selection of the category further text boxes are to be created dynamically depending upon the selection. I know how to get the selected value from $_POST but here i need it befor form submission.Pls help

Answer 1

You would need to use js. Either:

document.getElementById('elementName').value

or

document.formName.elementName.value

or

use jQuery.

Than if you need a response from a php script before submission you would need to use ajax.