Add enctype to form

Hi all.

I need to add a upload file a form module.
I have implemented this code and working fine

<?php

/**
 * Make the Give Donation form a multipart/form-data form
 *
 */

function give_add_multipart_tag_donation_form( $final_output, $args ) {
    $form_tag = "<form id=\"give-form-{$args['form_id']}-1\"";
	$final_output = str_replace( $form_tag, "{$form_tag} enctype=\"multipart/form-data\"", $final_output );

	return $final_output;
}

add_filter( 'give_donate_form', 'give_add_multipart_tag_donation_form', 10, 2 );

The problem arises when, in the same page, i have more form module.
The form id is so composed

<form id=”give-form-XXXXX-n”>

where
– XXXXX is the form-id;
– n is a progressive form number;

I don’t know how to do to implement the dynamic “n” in the code above.

Can you help me?

Regards,
Marco

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