Grabbing strings from an html source

whitchman

Ok lets say I want to look through a html source and pick out any links and put them in an array.

html page:

<html>
<head>
</head>
<body>
<p>
Some text <a href="page2.html">click here</a> More text <a href="page3.html">click here</a> Even more text <a href="page4.html">click here</a>
</p>
</body>
</html>

I'm guessing it goes something like this:

something opens and reads the file
something puts each line of the file into an array
something searches for each instance of: a href="*.html (the asterisk is a wildcard right?)
something takes each instance of: a href="*.html and puts whatever the wildcard found into a new array
now i can do whatever i want with it like print out a list of all the links it found

do I have any idea what I'm talking about?

The_Chancer

Yeah - looks like you need fopen() and a regular expression to filter the file, then set an array and array_push onto the end.

bubblenut

<?php
preg_match_all('/<a\\shref="([^"]+\.html)"[^>]>/',$filecontents,$matches);
for($i=0;$i<count($matches);$i++) {
  $output[]=$matches[$i][1];
}
?>

Well here's the regex part. $filecontents will be the text of the entire file. $output will be an array of all links to html files on the page.
HTH
Bubble

whitchman

ok cool. Could you explain what each part of the search pattern means? Like what does ^ do and what does [ do, etc?

TomD

http://www.php.net/manual/en/ref.pcre.php

whitchman

thanks but I still dont really understand how that search pattern works.

The_Chancer

I found this which I have found invaluable...

jebster

A great example by Weedpacket: http://www.phpbuilder.com/board/showthread.php?threadid=10223623#post10276943 😉 Explains everything too!

The_Chancer

Very true - he has said he would write a PHPBuilder tutorial - if he ever got the chance....