preg_match_all 未定义的偏移错误

Question

这里可能存在正则表达式错误，但我无法解决。

我收到“Undefined offset: 0”错误，无法获取标题的值。

这是我的代码。 INEEDTHISONE 是我要取的标题。

for ($j = 1; $j <= 1; $j++) {
    for ($i = 0; $i < 5; $i++) {
        $site = file_get_contents("http://example.com/index.php?route=product/category&path=395&page=$j");      
        preg_match_all('@<div class="name csstwo" title="INEEDTHISONE"><a itemprop="name" href="http://example.com/id/(.*?)/(.*?).html&amp;path=(.*?)">(.*?)</a></div>@', $site, $title);          
        $title[2][$i] = strip_tags($title[2][$i]); // strip tags
        $title[2][$i] = preg_replace('~.*?>~', '', $title[2][$i]); // remove a tag and messy stuff

        echo $title[2][$i]."<br>"; // gives undefined offset error.

}

详细错误。

第 24 行 = $title[2][$i] = strip_tags($title[2][$i]);

第 27 行 = echo $title[2][$i]."<br>";

Notice: Undefined offset: 0 in /Applications/MAMP/htdocs/test3.php on line 24

Notice: Undefined offset: 1 in /Applications/MAMP/htdocs/test3.php on line 27


Notice: Undefined offset: 1 in /Applications/MAMP/htdocs/test3.php on line 24


Notice: Undefined offset: 2 in /Applications/MAMP/htdocs/test3.php on line 24

Notice: Undefined offset: 1 in /Applications/MAMP/htdocs/test3.php on line 27


Notice: Undefined offset: 3 in /Applications/MAMP/htdocs/test3.php on line 24

Notice: Undefined offset: 1 in /Applications/MAMP/htdocs/test3.php on line 27


Notice: Undefined offset: 4 in /Applications/MAMP/htdocs/test3.php on line 24

Notice: Undefined offset: 1 in /Applications/MAMP/htdocs/test3.php on line 27

Answer 1

尝试更改以下内容：

for ($j = 1; $j <= 1; $j++) {
    for ($i = 0; $i < 5; $i++) {
        $site = file_get_contents("http://example.com.com/index.php?route=product/category&path=395&page=$j");      
        preg_match_all('@<div class="name csstwo" title="INEEDTHISONE"><a itemprop="name" href="http://example.com/id/(.*?)/(.*?).html&amp;path=(.*?)">(.*?)</a></div>@', $site, $title); 
        if(isset($title[2][$i])){
            $title[2][$i] = strip_tags($title[2][$i]); // strip tags
            $title[2][$i] = preg_replace('~.*?>~', '', $title[2][$i]); // remove a tag and messy stuff

            echo $title[2][$i]."<br>"; // gives undefined offset error.
        }
}

Answer 2

我变了

    preg_match_all('@<div class="name csstwo" title="INEEDTHISONE"><a itemprop="name" href="http://example.com/id/(.*?)/(.*?).html&amp;path=(.*?)">(.*?)</a></div>@', $site, $title);

至

    preg_match_all('@<div class="name csstwo" title="INEEDTHISONE"><a itemprop="name" href="http://example.com/id/(.*?)/(.*?).html&path=(.*?)">(.*?)</a></div>@', $site, $title);

问题解决了。

&amp;

导致了这个问题。

preg_match_all 未定义的偏移错误

preg_match_all undefined offset error

php

regex

file-get-contents

preg-match-all