Warning: Invalid argument supplied for foreach() in 问题

Question

菜鸟问题：
Warning: Invalid argument supplied for foreach() in F:\www\Order\index.php on line 37

Warning: Invalid argument supplied for foreach() in F:\www\Order\index.php on line 39

打开页面 提示以上问题 index.php
代码

$exts = $db->select_date('ext');
foreach($exts as $ext)
  $config['ext'][$ext['id']] = $ext;
foreach($exts as $ext)
  $config['ext'][$ext['code']] = $ext;

Answer 1

$exts不是数组且不是可迭代的对象