如何正确提取PHP字符串中分隔的标点符号和字符？

$string = "Hello, World! This is a sample string.";
$pattern = '/[\s,\.]+/'; // 匹配空格、逗号和句号

$result = preg_split($pattern, $string);
print_r($result);

Array
(
    [0] => Hello
    [1] => World
    [2] => This
    [3] => is
    [4] => a
    [5] => sample
    [6] => string
)

$string = "Hello, World! This is a sample string.";
$delimiters = " ,."; // 分隔符为空格、逗号和句号

$token = strtok($string, $delimiters);
while ($token !== false) {
    echo $token . "\n";
    $token = strtok($delimiters);
}

Hello
World
This
is
a
sample
string