如何检查数组的数组在PHP或Laravel中其值中是否具有键值对

Question

I have the following array. I want to know whether any of the values of the array contains the key-value pair "RoleCode" => "Admin" .

[
  0 => [
    "RoleCode" => "Admin"
    "RoleName" => "Administrator"
  ]
  1 => [
    "RoleCode" => "PM"
    "RoleName" => "ProjectManager"
  ]
  2 => [
    "RoleCode" => "ScheduleUser"
    "RoleName" => "Schedule User"
  ]
]

I can write a long code to find it out like the following:

$isAdmin = false;
foreach ($user['Roles'] as $role) {
    if ($role['RoleCode'] == 'Admin') {
        $isAdmin = true;
    }
}

Is there any way to do this in a better way?

Answer 1

You could use array_column() and in_array() :

$isAdmin = in_array('Admin', array_column($user['Roles'], 'RoleCode')) ;

• array_column() will return an array with all values from 'RoleCode' key
• in_array() will check if Admin is inside

Answer 2

It depends what is better way.

Current solution with adding break when item found:

$isAdmin = false;
foreach ($user['Roles'] as $role) {
    if ($role['RoleCode'] == 'Admin') {
        $isAdmin = true;
        break;
    }
}

will be O(n) in worst case.

Other solutions, like one in another answer

$isAdmin = in_array('Admin', array_column($user['Roles'], 'RoleCode'));

This will be O(n) + O(1) in best case and O(n) + O(n) in worst. More than initial foreach .

Another one is filtering:

$isAdmin = !empty(array_filter(
    $user['Roles'], 
    function ($v) { return $v['RoleCode'] == 'Admin'; }
));

It is always O(n)

So, from the point of readability and performance, initial code is the winner.