如何访问PHP多维数组的某些元素？

I have the following multidimensional array.

I have run a foreach loop and am trying to echo the client nicknames of the 2 users. The code I am running is as follows.

$client_r = $Ts3->clientList();

foreach ($client_r as $client)
    {
        echo $client['data']['client_nickname'];
    }

What am I doing wrong?

Try this:

foreach ($client_r as $client)
{
    echo $client['data'][0]['client_nickname'];
    echo $client['data'][1]['client_nickname'];

    // As there are further arrays inside array, so you have to include the index also
}

If you start from the data then your access will be easy-

In data you have again array, so the $client now stores the sub array, now you can easily access your client_nickname.

$client_r = $Ts3->clientList();

foreach ($client_r['data'] as $client){
    echo $client['client_nickname'];
}

This may be solve your problem.