<select  name="books[]" id="books" multiple="multiple">
<?php foreach($categories as $books_id=>$books){ ?>
<option value="<?php echo $books_id?>"<?php if(($this->input->post('books') && $this->input->post('books') == $books_id) || $data->question == $books_id) echo 'selected';?>>
<?php echo $books->books?></option>
<?php $value = json_decode($result->value);?>
<?php } ?>
</select>

add/view->

<select  name="books[]" id="books" multiple="multiple">
                                    <?php foreach($categories as $books){ ?>
                                        <option value="<?php echo $books->books_id?>" <?php if($this->input->post('books') == $books->books_id) echo 'selected';?>><?php echo $books->books?></option>
                                    <?php $books = json_decode($result->books);?>
                                    <?php } ?>
                                </select>

public function edit($books_id) {
        $this->data['categories']=$this->books_model->getcategories();
        $where = ' books_id = ? ';
        $where_data [] = $books_id;
        if ($this->input->post ()) {
            $update_data = array ();
            $update_data ['ques_id'] = json_encode($this->input->post ( 'question' ));
            $update_data ['quotes'] = $this->input->post ( 'quotes' );
            $update_data ['comment'] = $this->input->post ( 'comment' );
            $update_data ['status'] = ( int ) $this->input->post ( 'status' );
            $update_data ['Datetime'] = $this->books_model->getCurrentDatetime ();
            if (! $this->input->post ( 'old_image' )) {
                $field_name = 'image';
                $temp_file_name = $this->file [$field_name] ['name'];
                $file_name = time () . '_' . $this->randomString ( 10 ) . '.' . $this->getFileExtension ( $temp_file_name );

                if (! $this->uploadImage ( $this->upload_path, $file_name, $field_name )) {
                    $this->session->set_flashdata ( 'error', $this->file_error );
                }
                $this->createThumbnail ( $this->file_data ['full_path'], $this->upload_path . '/thumb/' . $file_name, 75, 50 );
                $update_data ['image'] = $file_name;
            }
            if (! $this->books_model->__update ( 'ph_books', $update_data, array (
                    'books_id' => $books_id
            ) )) {
                $this->session->set_flashdata ( 'error', 'Record couldn'n updated. Please try again.' );
            } else {
                $this->session->set_flashdata ( 'success', 'books updated successfully.' );
                //redirect ( 'admin/books' );
            }
        }
        $rs = $this->books_model->__select ( 'ph_books', '*', $where, $where_data );
        $result = $rs->result ();
        $this->data ['data'] = $result [0];

        $this->load->view ( 'admin/template/header' );
        $this->load->view ( 'admin/books/edit', $this->data );
        $this->load->view ( 'admin/template/footer' );
    }


function add() {
        $this->data['categories']=$this->books_model->getcategories();
        if ($this->input->post ()) {
            $insert_data = array ();
            $insert_data ['ques_id'] = json_encode($this->input->post ( 'question' ));
            $insert_data ['quotes'] = $this->input->post ( 'quotes' );
            $insert_data ['comment'] = $this->input->post ( 'comment' );
            $insert_data ['Datetime'] = $this->books_model->getCurrentDatetime ();
            $field_name ='image';
            $temp_file_name = $this->file[$field_name]['name'];
            $file_name = time().'_'.$this->randomString(10).'.'.$this->getFileExtension($temp_file_name);

            if(!$this->uploadImage($this->upload_path,$file_name,$field_name)){
                $this->session->set_flashdata('error', $this->file_error);
            }
            else{
                $insert_data['image'] = $file_name;
                $this->createThumbnail($this->file_data['full_path'], $this->upload_path.'/thumb/'.$file_name,75,50);
                if(!$this->books_model->__insert('ph_books',$insert_data)){
                    $this->session->set_flashdata('error', 'Record couldn'n inserted. Please try again.');
                }
                else{
                    $this->session->set_flashdata('success', 'books created.');
                    //redirect('admin/books');
                }
            }
        } $a=json_encode($this->input->post ( 'question' )); print_R($a);
        $this->load->view ( 'admin/template/header' );
        $this->load->view ( 'admin/books/add', $this->data );
        $this->load->view ( 'admin/template/footer' );
    }