如何从PHP中的数组中获取索引？

I a code like this

for($ctr=0; $ctr < 4; $ctr++) {
    $messages["message"] = $ctr;
    array_push($response["messages"], $messages);
}

I want to get the message that contains the value 2. How do I do that in PHP?

you have to use array search on this case.

for($ctr=0; $ctr < 4; $ctr++) {
    //$messages["message"] = $ctr;
    array_push($response, $ctr);
}
echo array_search('2', $response);

array search give you the index of the array which value is 2.

for($ctr=0; $ctr < 4; $ctr++) {
    $messages["message"] = $ctr;
    array_push($response["messages"], $messages);
}

function mysearch($val) {
    global $response;
    for ($i = 0; $i < count($response["messages"]); $i++) {
        if ($response["messages"][$i]["message"] === $val) {
            return $i;
        }
    }
    return -1;
}

echo mysearch(2); // will print the index, or -1 if not found