Update field on form submission

[Intelartifice]

Hello,
I'm trying to update value of a filed in an other list on form submission.

I tried with: $formModel->updateFormData('my_other_table___my_element', 'My_table___form_my_element', true);
I proceed onBeforeProcess
But it doesn't work and I understand why.

So I tried in this way but I get an error

$myId = (array) $formModel->formData['my_table___form_my_element'];
$query->update('my_other_table')->set('element = 'form_my_element')->where('id = ' . (int) $myId);
$db->setQuery($query);
$db->execute();

Any idea ?
Thanks,
Jean-Marc

 

[juuser]

What typeof element is "'my_table___form_my_element"?

What do you get as output after form submit when you add

var_dump($myId);
exit;

right after the line: $myId = (array) $formModel->formData['my_table___form_my_element'];