Tag: an object that implements Countable

Post Views: 22 1. Error: count(): parameter must be an array or an object that implements countable (view: ). as shown in Figure 1 2. Check the code implementation 3. Print $user->address_book, its value is null 4. Adjust the code implementation, when $user->address_book is null, the expression $user->address_book ??[]equivalent to[], otherwise it is $user->address_book. 5. In PHP 7.2.0, when the…