Rename the header “Invoice” to “Invoice-Number: [invoice-number]

I guess I have to use the following line next to the Invoice header?
<?php echo $this->order->get_invoice_number(); ?>

but I don’t see where the header “Invoice” is defined in the invoice.php

I’ve found this function

add_filter( ‘wpo_wcpdf_invoice_title’, ‘wpo_wcpdf_invoice_title’ );
function wpo_wcpdf_invoice_title () {
$invoice_title = ‘Tax Invoice’;
return $invoice_title;
}

mmmh, if I would know php, I’d know how to put $this->order->get_invoice_number(); into that function

Hi @mappel,

The easiest way to do this is with our Professional extension. This will let you add the invoice number to the document title right in the plugin settings.

You can indeed also use an action hook:

add_filter( 'wpo_wcpdf_invoice_title', 'wpo_wcpdf_add_invoice_number', 10, 2 );
function wpo_wcpdf_add_invoice_number ( $title, $document = null ) { 
	if ( !empty($document) && !empty( $document->order ) ) {
		$invoice = wcpdf_get_invoice( $document->order );
		$invoice_number = $invoice->get_invoice_number();
		$title .= " - " . $invoice_number;
	}
	return $title;    
}

This would go into the functions.php of your child theme. If you haven’t worked with action hooks or functions.php before please read this: How to use filters

so generous from you to provide the hook for my request!
thank you very much. it works perfectly!!