[TYPO3-mvc] "Model->attach" does not change database

[Yann PETIT]

Bonjour,

Sorry, it is surely a stupid problem, but i am stuck.

In a model, I have something like this :
---------------------------------------------------------------------------------
/**
  * Foreign table objects list
  *
  * @var 
Tx_Extbase_Persistence_ObjectStorage<Tx_MyExt_Domain_Model_Foreignclass>
  * @lazy
  */
 protected $foreignclass;

/**
  * Add a foreign object in the list
  *
  * @param Tx_MyExt_Domain_Model_Foreignclass $foreignobject
  * @return void
  */

 public function addForeignclass(Tx_442_Domain_Model_Joueurl1 
$foreignobject) {
        var_dump($foreignobject); // Valid Object is returned
        $this->foreignclass->attach($foreignobject);  // No Error is 
dsiplayed
 }
-------------------------------------------------------------------------------------

In the controller, I have :
-------------------------------------------------------------------------------------
$model->addForeignclass($foreignobject);
return($model->getForeignclass());     //Gives me the good number of objects 
(including the new one)
------------------------------------------------------------------------------------

But nothing appends in the database.

Tank you in advance for help

Yann PETIT