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[isedeasy]

I did a quick google search and a forum search but could not find anything to help me (may be searching with the wrong words).

 

Basically I want to check if URL that a user inputs exists in my database. the problem I have is that it may exist just in a slightly different format, for example.

 

http://google.com

http://www.google.com

www.google.com

www.google.com/

www.google.com/index.html

 

These are all the same url but if I treat them as stings they are obviously different, How would I go about this? Im guessing I need to format the strings before I check/insert into database?

 

Is there already a function out there that does this?

 

Cheers

[mrMarcus]

what's common about all of those?  google.com

 

you can use either regex or explode() on the vars.

 

the most efficient thing to do would be to normalize the data going into the db so that it is easy to cross-reference, ie.

 

upon inputting the domain name into the db to begin with, strip any .com's, www.'s, http://'s, etc., or any other attributes that you feel like .. this way, you always know what to check against in the db, making life much easier.

 

gotta run, otherwise i would've left some examples .. hopefully somebody else will pick up where i left off.

[isedeasy]

That makes sense, that's what I thought I would need to do.

 

Cheers

[isedeasy]

Ok I think I pretty much have it, its not very pretty but it seems to work

 

<?php
function formatURL($url) {

	//an array of strings I wish to remove
	$remove = array(
					"http://",
					"www.",
					"index.html",
					"index.php"
					);

	//loop through array
	foreach($remove as $value) {
		//replace array values with nothing
		$url = str_ireplace($value, '', $url);
	}

	//if the url ends in a / then trim it off
	$url = rtrim($url,'/');

	return $url;

}

if (isset($_POST['test'])) {

	echo '<h1>'.formatURL($_POST['url']).'</h1>';

}

?>

<form action="<?php echo $_SERVER['PHP_SELF'] ?>" method="post">

<input type="text" size="80" name="url"/>
<input type="submit" name="test"/>

</form>

 

Any feedback would be appreciated.

[Robbrad]

Not bad but what happens when you get sub domains? eg adwords.google.com

 

do you want to exclude them also?

[isedeasy]

No not if it points to a different page, basically I don't want somebody to be able to add a link to a page that already exists in my database.

 

I can already spot an issue though just be looking at the url to this page

 

 

[Robbrad]

Try..

 

function isURL($url) {
        
      $protocol = '(http://|https://)';
        $allowed = '([a-z0-9]([-a-z0-9]*[a-z0-9]+)?)';

        $regex = "^". $protocol .// must include the protocol
                         '(' . $allowed . '{1,63}\.)+'. // 1 or several sub domains with a max of 63 chars
                         '[a-z]' . '{2,6}'; // followed by a TLD
        

$trimmedURL = preg_replace($regex, "", $url);
return $trimmedURL;
}

$newURL = isURL($url);