在多選下拉菜單中設置多個默認選定值

Question

// Get Series List 
    $this->load->model('Series_model'); 
    $serieslist = $this->Series_model->gettypelist($userid, 'e'); 

    $series_item_id = 0; 

    $this->db->select('series_id'); 
    $this->db->where('type_id', 13); 
    $this->db->where('series_type', 'e'); 
    $series_item_query = $this->db->get('series_items'); 

    if ($series_item_query->num_rows() > 0) { 
     $series_item_id = $series_item_query->result(); 
    } 
    //print_r($series_item_id); 

    $data['serieslist'] = '<select name="series_id[]" class="type input_select" multiple="multiple">'; 
    $data['serieslist'] .= '<option value="">None</option>'; 
    foreach ($serieslist as $list) { 
     $data['serieslist'] .= '<option value="' . $list->id . '" ' . ($series_item_id[0]->series_id === $list->id ? 'selected="selected"' : '') . '>' . $list->title . '</option>'; 
    } 
    $data['serieslist'] .= '</select>'; 

上面是我正在使用的代碼。我希望能夠做的是爲選擇下拉菜單的多個值設置多個selected =「selected」。因此，例如：

<select name="series_id[]" class="type input_select" multiple="multiple"> 
    <option value="">None</option> 
    <option value="4">Event Series: Test 1</option> 
    <option value="5">Event Series: Test 2</option> 
    <option value="16">Event Series: Test 3</option> 
    <option value="17">Event Series: Test 4</option> 
    <option value="18">Event Series: Test 5</option> 
    <option value="19">Event Series: Test 6</option> 
    <option value="20">Event Series: Test 7</option> 
    <option value="21">Event Series: Test 8</option> 
</select> 

我想的4 16和19的選項值被選擇=「選擇」，但在我的代碼以上它只選擇4，然後停止。我錯過了什麼？如果您需要更多信息，請告訴我。

在此先感謝。

編輯：

的print_r的結果：

Array ([0] => stdClass Object ([series_id] => 4) [1] => stdClass Object ([series_id] => 16) [2] => stdClass Object ([series_id] => 19)) 

更新代碼：

foreach ($serieslist as $list) { 
     $data['serieslist'] .= '<option value="' . $list->id . '" ' . (in_array($list->id, $series_item_id, TRUE) ? 'selected="selected"' : '') . '>' . $list->title . '</option>'; 
    } 

上面更新代碼不起作用。

Answer 1

你比較$list->id先$ series_item_id：$ series_item_id [0] - > series_id

你需要把其他foreach在現有的一個：

foreach ($serieslist as $list) { 
    foreach ($series_item_id as $series_item) { 
     $data['serieslist'] .= '<option value="' . $list->id . '" ' . ($series_item->series_id === $list->id ? 'selected="selected"' : '') . '>' . $list->title . '</option>'; 
    } 
} 

或取series_id作爲陣列和使用in_array()：

$series_array = array(); 

foreach ($series_item_id as $series_item) { 
    $series_array[] = $series_item->series_id; 
} 

foreach ($serieslist as $list) { 

     $data['serieslist'] .= '<option value="' . $list->id . '" ' . (in_array($series_array, $list->id) ? 'selected="selected"' : '') . '>' . $list->title . '</option>'; 

}