需要帮助了解如何循环一个函数

Question

I'm creating a function that passes a URL over and gets the content of the page. If this page contains "Next>", I would like to grab the url of that and continue onto the page next under the page doesn't contain next anymore.

How would this be done? a while loop?

check_url("http://site.com");
-> url contains 'next', href is http://site.com/ggkdoe

-> does http://site.com/ggkdoe contain next? if so, hit it again and check if that contains 'next' then get that url etc etc

Understand? How can this be done?

Thank you in advance

Answer 1

Most likely something like this:

<?php
$checkNext = false;
$currentURL = "http://site.com";
do {
    $check = check_url($currentURL);
    if ($check !== null) {
       $currentURL = $check;
       $checkNext = true;
    } else {
       $checkNext = false;
    }
} while ($checkNext);

And I assume that check_url() will return an URL if one could be found and null otherwise. The do-while-loop ensures that the check is done at least once for the initial URL and afterwards again as long as check_url() could find another URL. At the end use $currentURL for whatever you want to do with that.