Question

I have an HTML form whose action should be set dynamically through JavaScript. How do I do it?

Here is what I am trying to achieve:

<script type="text/javascript">
    function get_action() { // Inside script tags
        return form_action;
    }
</script>

<form action=get_action()>
    ...
</form>

Answer 1

You cannot invoke JavaScript functions in standard HTML attributes other than onXXX. Just assign it during window onload.

<script type="text/javascript">
    window.onload = function() {
        document.myform.action = get_action();
    }

    function get_action() {
        return form_action;
    }
</script>

<form name="myform">
    ...
</form>

You see that I’ve given the form a name, so that it’s easily accessible in document.

Alternatively, you can also do it during submit event:

<script type="text/javascript">
    function get_action(form) {
        form.action = form_action;
    }
</script>

<form onsubmit="get_action(this);">
    ...
</form>