按条件在多维数组上的PHP array_filter（）

Question

I've the below array of users:

$users = [
  [name => 'Alice', age => 22],
  [name => 'Bob', age => 23],
  [name => 'Charlie', age => 19]
];

I'd like to create an array of users that are at least 20 years old. I tried:

$allowed_users = array_filter($users, function($user) {
  return $user->age >= 20;
});
var_dump($allowed_users);

Which returns an empty array. I suppose I'm doing something wrong with the callback function.

Answer 1

You are using object notation with an array. It's a simple fix:

$users = [
  ['name' => 'Alice', 'age' => 22],
  ['name' => 'Bob', 'age' => 23],
  ['name' => 'Charlie', 'age' => 19]
];

$allowed_users = array_filter($users, function($user) {
  return $user['age'] >= 20;
});
var_dump($allowed_users);

And although it's not an error in itself, use quotes in your keys, otherwise the interpreter will throw a notice.