How to unset an element in this array in PHP

Question

I have an array with a structure like this. Now I would like to unset the "answer" element. How should I do this using unset() or similar PHP functions?

[style] => light
[buttons] => Array (
    [flag] => Array (
        [tags] => name="q_doflag" onclick="qa_show_waiting_after(this, false);"
        [label] => Flag this
        [popup] => Flag this thing 
        )
    [answer] => Array (
        [tags] => name="q_doanswer" id="q_doanswer" onclick="return qa_toggle_element('anew')"
        [label] => answer this
        [popup] => Answer this button
        )
    )

Answer 1

I think I solved my problem.
Here's what I did:

unset($array['buttons']['answer']);

Comments

That looks about right if you want to remove the entire key.

– Ansgar Wiechers 2020-10-08

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FTR, it's perfectly fine to accept your own answer, since it's a solution you found yourself.

– Ansgar Wiechers 2020-10-08

Answer 2

Depends on what result exactly you want to achieve. Do you want to remove just the value of the "answer" key, replace the value with a different value, or remove the key entirely?

I'll be using the following simplified data structure for demonstration purposes:

php > $a = Array("a" => Array("b" => 2, "c" => Array("d" => 4, "e" => 5)));
php > print_r($a);
Array
(
    [a] => Array
        (
            [b] => 2
            [c] => Array
                (
                    [d] => 4
                    [e] => 5
                )
        )
)

To remove just the value of the (sub)key "c" you'd assign NULL to the key:

php > $a['a']['c'] = NULL;
php > print_r($a);
Array
(
    [a] => Array
        (
            [b] => 2
            [c] => 
        )
)

Similarly you'd assign the new value if you wanted to replace the current value:

php > $a['a']['c'] = Array("x" => "foo", "y" => "bar");
php > print_r($a);
Array
(
    [a] => Array
        (
            [b] => 2
            [c] => Array
                (
                    [x] => foo
                    [y] => bar
                )
        )
)

If you want to remove the key entirely you'd use the unset() function, as you've already discovered:

php > unset($a['a']['c']);
php > print_r($a);
Array
(
    [a] => Array
        (
            [b] => 2
        )
)