PHP strtok（）如果我理解这一点，请告诉我

Question

This is the the code:

<?php
    $string = 'Hey there buddy';
    $token = strtok($string, ' ');
    while($token !== false)
    {
        echo $token."<br/>";
        $token = strtok(' ');
    }
?>

I just want to know if I understand this right. Here is what I think about strtok(). To use strtok(), first, you have to set it to a variable($token in this case) with input string ($string in this case) and a separator (' ' in this case). And then you have to use it again in a while loop but this time only specify a separator not the input string because it's already connected to variable $string at the time we first used it. Am I right?

Answer 1

Yes, strtok keeps an internal buffer from the first population with $string. It subsequently returns parts of that; whenever you pass it just a new character to split with.

You can shorten your loop with a do/while construct, btw:

do {
    echo $token."<br/>";
}
while (is_str($token = strtok(' ')));

That's also the drawback of strtok however. Since it works on an globally-internal string buffer, you can only ever use one such loop - it's unsuited to delimit substrings in parallel or work on another buffer alongside.

Though when you're just splitting with one delimiter, you might as well use PHPs most overused function: explode.