php通知（试图获取非对象的属性）错误

Question

So, I have following php for wp:

 $usersNames = array();
 foreach ($userIDs as $userId) {
            $userInfo = get_userdata($userId);
            $usersNames[] = $userInfo->display_name; //this one                                     
        } 

I am getting an error for $usersNames .

"PHP Notice:  Trying to get property of non-object in /functions.php on line"

What is going on?

Any suggestions?

Thanks

EDIT:

So, for $userIDs , I have an array of user ids. Then I am trying to get user display name etc for individual ids.

Answer 1

Your function get_userdata() will return False on failure, WP_User object on success.

And error Trying to get property of non-object means that this function has returned false .

Simply check if $userInfo is not empty

$userInfo = get_userdata($userId);

if (!empty($userInfo)) {
    $usersNames[] = $userInfo->display_name;
}

Answer 2

you need judge whether $userInfo return the right obj

  $usersNames = array(); foreach ($userIDs as $userId) { $userInfo = get_userdata($userId); $usersNames[] = isset($userInfo->display_name)?$userInfo->display_name:''; //this one }