Yii2 foreach 报错， Undefined index: id但确实定义了！

正常

php

<ul class="list-unstyled">
    <?php foreach( Yii::$app->params['area'] as $k => $row): ?>
    <li><a href=""><?php var_dump($row); ?></a></li>
    <?php endforeach; ?>
 </ul>

有输出

array (size=9)
  'id' => string '19' (length=2)
  'name' => string '广东' (length=6)
  'pinyin' => string '' (length=0)
  'level' => string '1' (length=1)
  'upid' => string '0' (length=1)
  'sortid' => string '1' (length=1)
  'hit' => string '439' (length=3)
  'thumb' => string '' (length=0)
  'sub' => 
    array (size=0)
      empty

报错

php<ul class="list-unstyled">
    <?php foreach( Yii::$app->params['area'] as $k => $row): ?>
    <li><a href=""><?php var_dump($row['id']); ?></a></li>
    <?php endforeach; ?>
 </ul>

报错提示：

Undefined index: id

---

看一下

if (!isset($row['id'])) {
    var_dump($row);
}