PHP - Add link to a URL in a string

Question

I have a function that will add the <a href> tag before a link and </a> after the link. However, it breaks for some webpages. How would you improve this function? Thanks!

function processString($s) 
{
    // check if there is a link

    if(preg_match("/http:\/\//",$s))
    {
        print preg_match("/http:\/\//",$s);


        $startUrl =  stripos($s,"http://");

        // if the link is in between text
        if(stripos($s," ",$startUrl)){
            $endUrl = stripos($s," ",$startUrl);
        }
        // if link is at the end of string
        else {$endUrl = strlen($s);}

        $beforeUrl = substr($s,0,$startUrl);
        $url = substr($s,$startUrl,$endUrl-$startUrl);
        $afterUrl = substr($s,$endUrl);

        $newString = $beforeUrl."<a href=\"$url\">".$url."</a>".$afterUrl;

        return $newString;
    }

    return $s;
}

The regex is a little sloppy, but 99% of my input will have correct URLs if any — AlexBrand
– AlexBrand, Commented Nov 18, 2010 at 16:53
At the beginning you test agains https also, but later you omit the "s". Dont know, if this cause this error, because I also dont know, which pages are broken ;) — KingCrunch
– KingCrunch, Commented Nov 18, 2010 at 16:58
Sorry, I removed the [s] from the regex. How could I include functionality for strings such as "www.google.com", or "https:www.example.com" ? — AlexBrand
– AlexBrand, Commented Nov 18, 2010 at 17:00
"www.google.com" is going to be harder to parse. you need a long regex just to accommodate all TLDs. — bcosca
– bcosca, Commented Nov 18, 2010 at 17:03

Aron Rotteveel · Accepted Answer · 2014-07-24 07:22:35Z

21

function processString($s) {
    return preg_replace('/https?:\/\/[\w\-\.!~#?&=+\*\'"(),\/]+/','<a href="$0">$0</a>',$s);
}

edited Jul 24, 2014 at 7:22

Aron Rotteveel

83.4k17 gold badges106 silver badges129 bronze badges

answered Nov 18, 2010 at 16:57

bcosca

17.6k5 gold badges43 silver badges51 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

Narcolessico Over a year ago

I think a "=" is missing: it fails when the url contains get parameters. I just added it after the "&" and now it works: preg_replace('/https?:\/\/[\w\-\.!~?&=+\*\'"(),\/]+/','<a href="$0">$0</a>',$s)

Roman S Over a year ago

You forgot about addresses with # inside - so more correct version is preg_replace('/https?:\/\/[\w\-\.!~#?&=+\*\'"(),\/]+/','<a href="$0">$0</a>',$text)

Aron Rotteveel Over a year ago

I just edited the answer to reflect these two additions.

Alcalyn Over a year ago

Do not forget to add the 'u' modifier if your string may contains utf8 characters

sNICkerssss Over a year ago

I add one more char "%". As result: '/https?:\/\/[\w\-%\.!~#?&=+*\'"(),\/]+/','<a href="$0">$0</a>'

tdammers · Accepted Answer · 2010-11-18 16:57:49Z

1

It breaks for all URLs that contain "special" HTML characters. To be safe, pass the three string components through htmlspecialchars() before concatenating them together (unless you want to allow HTML outside the URL).

answered Nov 18, 2010 at 16:57

tdammers

20.7k1 gold badge41 silver badges57 bronze badges

Comments

egze · Accepted Answer · 2010-11-18 17:05:15Z

1

function processString($s){
  return preg_replace('@((https?://)?([-\w]+\.[-\w\.]+)+\w(:\d+)?(/([-\w/_\.]*(\?\S+)?)?)*)@', '<a href="$1">$1</a>', $s);
}

Found it here

answered Nov 18, 2010 at 17:05

egze

3,24626 silver badges23 bronze badges

1 Comment

Yuv Over a year ago

The same scenario I need it in Jquery/Javascript. Can anyone help ?

Collectives™ on Stack Overflow

PHP - Add link to a URL in a string

3 Answers 3

5 Comments

Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

5 Comments

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related