在codeigniter中添加两个数组变量

I am building a system where i need to update the value in the database field but before doing that i need to take the current value in the database then adding it to the current value the following is a code from the controller.

public function transfer_amount(){



    $email  =  $this->input->post('view');

    $this->load->model('user_model');

    $data['user_balance'] = $this->user_model->fetch_balance($email);

    $data['balance'] = $this->input->post('amount');

    $data['total'] = $this->math->add($data['balance'],$data['user_balance']);


    $data = array(

            'balance' => $data['total'],

    );




    if($this->user_model->transfer_amount($data,$email)== true){


        $this->load->view('layer_service/success',$data);


    }
    else
    {


        $this->load->view('layer_service/unsuccessfull',$data);
    }



}

}

then the code in the module that fetch the current balance from the database is as following.

 function fetch_balance($email){


    $this->db->select('balance');
    $this->db->from('tbl_users');
    $this->db->where('email', $email);

    $query = $this->db->get();
    $result = $query->result();

    return $result;


}

not sure but look at this part - don't call it $data because i think thats messing you up later

for example call it $balance

  $balance = array(

            'balance' => $data['total'],

    );

    // pass the $balance to your model method
    if($this->user_model->transfer_amount($balance,$email) == true){

       // keeping $data here to pass to the view 
        $this->load->view('layer_service/success',$data);

    }

getting the balance should be wrapped in an if in case it fails

if( ! $data['user_balance'] = $this->user_model->fetch_balance($email) )
{
   $this->_showNoUserFor($email) ; 
} 

another suggestion:

$email  =  $this->input->post('view');

validate the email first before sending it to your database table. codeigniter form validation library works really well.

======

EDIT ok this part

 $data['total'] =   $this->math->add($data['balance'],$data['user_balance']);

means that you have a model called math with a method called add() so if you don't have that you would just use php math which is very simple

$data['total'] = $data['balance'] + $data['user_balance'] ; 

of course this assumes everything has been validated first so you are actually adding together two numbers.