$this->data dosen't work

[eluser]mostafash[/eluser]
Hi there,
I want to retrieve session->flashdata from session->set_flashdata and send it to a form.But I have this problems:
1.if I use

Code:

$data['message'] = $this->session->flashdata('message');

instead of

Code:

$this->data['message'] = $this->session->flashdata('message');

,that don't send value to my form.
2.When I want to send multi session data like :

Code:

$this->data['message']    = $this->session->flashdata('message');
$this->data['message1']  = $this->session->flashdata('message1');
$this->data['message2']  = $this->session->flashdata('message2');

,that just use first line , other variables ( $this->data['message1'],$this->data['message2'] ) was 'Undefined'.
How can I fix this problem?
help me please