Parse All Links That Contain A Specific Word In "href" Tag

Question

Possible Duplicate:
Grabbing the href attribute of an A element

I need to parse all links of an HTML document that contain some word (it's always different).

Example:

<a href="/bla:bla">BLA</a>
<a href="/link:link">BLA</a>
<a href="/link:bla">BLA</a>

I only need the links with "href=/link: ...." what's the best way to go for it?

$html = "SOME HTLM ";
$dom = new DomDocument();
@$dom->loadHTML($html);
$urls = $dom->getElementsByTagName('a');
foreach ($urls as $url)
{
    echo "<br> {$url->getAttribute('href')} , {$url->getAttribute('title')}";
    echo "<hr><br>";
}

In this example all links are shown, I need specific links.

Lawrence Cherone · Accepted Answer · 2011-11-21T07:10:04.713

5

By using a condition.

<?php 
$lookfor='/link:';

foreach ($urls as $url){
    if(substr($url->getAttribute('href'),0,strlen($lookfor))==$lookfor){
        echo "<br> ".$url->getAttribute('href')." , ".$url->getAttribute('title');
        echo "<hr><br>";
    }
}
?>

edited Nov 21 '11 at 07:10

answered Nov 21 '11 at 06:58

Lawrence Cherone

46,049
7
62
106

score 3 · Answer 2 · edited May 23 '17 at 12:03

Instead of first fetching all the a elements and then filtering out the ones you need you can query your document for those nodes directly by using XPath:

//a[contains(@href, "link:")]

This query will find all a elements in the document which contain the string link: in the href attribute.

To check whether the href attribute starts with link: you can do

//a[starts-with(@href, "link:")]

Full example (demo):

$dom = new DomDocument();
$dom->loadHTML($html);
$xpath = new DOMXPath($dom);
foreach ($xpath->query('//a[contains(@href, "link:")]') as $a) {
    echo $a->getAttribute('href'), PHP_EOL;
}

Please also see

for related questions.

Note: marking this CW because of the many related questions

Thank you.Would you also explain what "CW" is? – Ron Nov 22 '11 at 18:32 — Ron, Nov 22 '11 at 18:32
@Ron CW = Community Wiki. I dont get reputation from it. – Gordon Nov 22 '11 at 19:03 — Gordon, Nov 22 '11 at 19:03

score 0 · Answer 3 · answered Nov 21 '11 at 06:57

0

Use regular expressions.

foreach ($urls as $url)
{
    $href = $url->getAttribute('href');
    if (preg_match("/^\/link:/",$href){
        $links[$url->getAttribute('title')] = $href;
    }
}

$links array contains all of the titles and href's that match.

answered Nov 21 '11 at 06:57

Mario Lurig

783
1
6
16

1

Regular expressions are relatively expensive operations, you should avoid using them in loops if possible. substr() is fine in this case. – GordonM Nov 21 '11 at 07:03
True, but judging by his setup, I have a strange feeling it was going to get more complicated later. – Mario Lurig Nov 21 '11 at 16:14
1

No need to add complexity until it's really needed :) – GordonM Nov 21 '11 at 16:15

score 0 · Answer 4 · answered Nov 21 '11 at 07:01

0

As getAttribute simply returns a string you only need to check what it starts with with strpos().

$href = $url -> getAttrubute ('href');
if (strpos ($href, '/link:') === 0)
{
    // Do your processing here
}

answered Nov 21 '11 at 07:01

GordonM

31,179
15
87
129

Parse All Links That Contain A Specific Word In "href" Tag

4 Answers4

Full example (demo):

Linked

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