Add to cart button, which php file calls?

[DarthFener]

In product.tpl,I have to send some information (textfield) of the product form to the Cart.php, but it seems that the $_POST variable (or Tools::getValue) is empty, so I think that the php file is another.

 

The "action" attribute of product.tpl is

 

$link->getPageLink('cart')

 

but actually, I don't know the exact php file. 

 

Do you know which php file is?

[DarthFener]

Information:

I read the function Link->getPageLink and all the operations is doing is:

 

$controller = Tools::strReplaceFirst('.php', '', $controller);

 

so it returns $controller which will be "Cart.php".

 

But Why I can't read the $_POST fields? where do I am wrong doing this:

 

$this->altezza = $_POST['altezza'];

$this->larghezza = Tools::getValue("larghezza");

 

where in the cart form of the product:

 

<label>{l s='Base (cm)'}</label>

<input type="text" name="altezza" id="altezza" class="text" />

<label>{l s='Altezza (cm)'}</label>

<input type="text" name="larghezza" id="larghezza" class="text"/>