Preg_match_all 分类: 技术问答 • 2022-04-17 17:40:16

Question

Hello i want to extract links <a href="/portal/clients/show/entityId/2121" > and i want a regex which givs me /portal/clients/show/entityId/2121 the number at last 2121 is in other links different any idea?Preg_match_all <a href

Answer 1

正则表达式解析链接是这样的：

'/<a\s+(?:[^"'>]+|"[^"]*"|'[^']*')*href=("[^"]+"|'[^']+'|[^<>\s]+)/i' 

既然是多么的可怕，我会建议使用Simple HTML Dom至少得到链接。然后你可以在链接href中使用一些非常基本的正则表达式来检查链接。

Answer 2

Paring links from HTML can be done using am HTML parser.

When you have all links, simple get the index of the last forward slash, and you have your number. No regex needed.

Answer 3

Simple PHP HTML Dom Parser例如：

// Create DOM from string 
$html = str_get_html($links); 

//or 
$html = file_get_html('www.example.com'); 

foreach($html->find('a') as $link) { 
    echo $link->href . '<br />'; 
} 

Answer 4

当“解析”HTML我主要依靠PHPQuery：http://code.google.com/p/phpquery/，而不是正则表达式。

Answer 5

Don't use regular expressions for proccessing xml/html。这可以很容易地使用来完成的builtin dom parser：

$doc = new DOMDocument(); 
$doc->loadHTML($htmlAsString); 
$xpath = new DOMXPath($doc); 
$nodeList = $xpath->query('//a/@href'); 
for ($i = 0; $i < $nodeList->length; $i++) { 
    # Xpath query for attributes gives a NodeList containing DOMAttr objects. 
    # http://php.net/manual/en/class.domattr.php 
    echo $nodeList->item($i)->value . "<br/>\n"; 
} 

Answer 6

这是我的解决方案：

<?php 
// get links 
$website = file_get_contents("http://www.example.com"); // download contents of www.example.com 
preg_match_all("<a href=\x22(.+?)\x22>", $website, $matches); // save all links \x22 = " 

// delete redundant parts 
$matches = str_replace("a href=", "", $matches); // remove a href= 
$matches = str_replace("\"", "", $matches); // remove " 

// output all matches 
print_r($matches[1]); 
?> 

我建议避免使用基于XML解析器，因为你不会总是知道， 文档是否/网站已经形成良好。

祝你好运