通过PHP脚本从JSON提取文本，其中JSON输入未知

<?php
function extractTextFromJSON($json) {
    $data = json_decode($json, true);
    $text = '';

    if (is_array($data)) {
        foreach ($data as $key => $value) {
            if (is_array($value) || is_object($value)) {
                $text .= extractTextFromJSON(json_encode($value));
            } else {
                $text .= $value . ' ';
            }
        }
    } elseif (is_object($data)) {
        foreach ($data as $key => $value) {
            if (is_array($value) || is_object($value)) {
                $text .= extractTextFromJSON(json_encode($value));
            } else {
                $text .= $value . ' ';
            }
        }
    }

    return $text;
}

$json = '{"name": "John", "age": 30, "city": "New York"}';
$text = extractTextFromJSON($json);
echo $text;
?>

John 30 New York