传递数组以在PHP中查看和显示数据

 private function displayallsurveys() {
    $this->load->database();
    $sql = "SELECT * from survey";
    $query = $this->db->query($sql);
    $data = array();
    if ($query->num_rows() > 0) {

       $data = $query->result_array();

       return $data;


    } else {
        return $data;
    }
}

Passing to the View

    $data = $this->displayallsurveys();
    $this->load->view('SurveyPage', $data);

When i show it on the from end

<ul class="nav nav-sidebar">
        <li class="active"><a href="#">Home</a></li>
        <li><a href="#">Add new Survey</a></li>
       <?php  foreach ($data as $row) {
            $SurveyTitle = $row['SurveyTitle'];
            $SurveyId = $row['SurveyId'];


                  echo'<li id=' . $SurveyId . '><a href=' . $SurveyTitle . '>' . $SurveyTitle . '</a><li>';
       }

          ?>

      </ul>

I am getting undefined variable $data

Please someone help

if you wanted to use $data variable in the view then you would need to pass it as

$this->load->view('SurveyPage', array('data' => $data));

Otherwise with the following the array keys becomes the variable names

$this->load->view('SurveyPage', $data);

Pass data like this

$data['data'] = $this->displayallsurveys();
$this->load->view('SurveyPage', $data);

Do it like:

$data['data'] = $this->displayallsurveys();
$this->load->view('SurveyPage', $data);

As a practice, it is recommended to use $data[] variable as a container of all variables you want to pass to a view. All you just have to do is name the key of each.

Example:
$data['survey'] = $this->displayallsurveys();
$this->load->view('SurveyPage', $data);

Then in view :

<ul class="nav nav-sidebar">
        <li class="active"><a href="#">Home</a></li>
        <li><a href="#">Add new Survey</a></li>
       <?php  foreach ($survey as $row) {
            $SurveyTitle = $row['SurveyTitle'];
            $SurveyId = $row['SurveyId'];


                  echo'<li id=' . $SurveyId . '><a href=' . $SurveyTitle . '>' . $SurveyTitle . '</a><li>';
       }

          ?>

      </ul>

Notice :

foreach ($survey as $row)