add id_order in the object of the mail order.conf

[giuliopowa]

hello,

i want add id_order in the object of the mail I send the customer ( order.conf ) 

I have already changed this line 256-257 in file mail.php in classes/
 

/* Create mail and attach differents parts */

$message = new Swift_Message('['.Configuration::get('PS_SHOP_NAME', null, null, $id_shop).'] '.$subject  ."-" .$to_name ."-" .$id_order);

I would like the subject of the mail is this:

name of shop(PS_SHOP_NAME) - order confirmation(.$subject) - customer name(.$to_name) - order id (.$id_order)

but the id_order does not appear because the variable does not exist. I tried to insert it but without success.

please help me  thanks !

ps: the picture is my hotmail
 

[giuliopowa]

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Edited January 30, 2015 by giuliopowa (see edit history)