Match URL pattern in PHP using a regular expression

I want to match a URL link in a wall post and replace this link with anchor tag. For this I use the regular expression below.

I would like the match four types of URL:

1. http://example.com
2. https://example.com
3. www.example.com
4. example.com

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

This expression matches only first two types of URL.

If I use this expression for matching a URL pattern, '@(www?([-\w\.]+)+(:\d+)?(/([\w/_\.]*(\?\S+)?)?)?)@', it only matches the third type of URL pattern.

How can I match all four typeS of URL patternS with a single regu开发者_运维百科lar expression?

I'd use a different regex to be honest. Like this one that Gruber posted in 2009:

\b(([\w-]+://?|www[.])[^\s()<>]+(?:\([\w\d]+\)|([^[:punct:]\s]|/)))

Or this updated version that Gruber posted in 2010 (thanks, @IMSoP):

(?i)\b((?:[a-z][\w-]+:(?:/{1,3}|[a-z0-9%])|www\d{0,3}[.]|[a-z0-9.\-]+[.][a-z]{2,4}/)(?:[^\s()<>]+|\(([^\s()<>]+|(\([^\s()<>]+\)))*\))+(?:\(([^\s()<>]+|(\([^\s()<>]+\)))*\)|[^\s`!()\[\]{};:'".,<>?«»“”‘’]))

A complete working example using Nev Stokes' given link:

public function clickableUrls($html){
    return $result = preg_replace(
        '%\b(([\w-]+://?|www[.])[^\s()<>]+(?:\([\w\d]+\)|([^[:punct:]\s]|/)))%s',
        '<a href="$1">$1</a>',
        $html
    );
}

I looked around and didn't see any that were exactly what I needed. I found this one that was close, so I modified it as follows:

^((([hH][tT][tT][pP][sS]?)\:\/\/)?([\w\\-]+(\[\w\.\&%\$\-]+)*)?((([^\s\(\)\<\>\\\"\.\   [\]\,;:]+)(\.[^\s\(\)\<\>\\\"\.\[\]\,;:]+)*(\.[a-zA-Z]{2,4}))|((([01]?\d{1,2}|2[0-4]\d|25[0-5])\.){3}([01]?\d{1,2}|2[0-4]\d|25[0-5])))(\b\:(6553[0-5]|655[0-2]\d|65[0-4]\d{2}|6[0-4]\d{3}|[1-5]\d{4}|[1-9]\d{0,3}|0)\b)?((\/[^\/][\w\.\,\?\'\\\/\+&%\$#\=~_\-]*)*[^\.\,\?\"\'\(\)\[\]!;<>{}\s\x7F-\xFF])?)$

Check it out on debuggex.

Use:

preg_match("/^((https|http|ftp)\:\/\/)?([a-z0-9A-Z]+\.[a-z0-9A-Z]+\.[a-z0-9A-Z]+\.[a-zA-Z]{2,4}|[a-z0-9A-Z]+\.[a-z0-9A-Z]+\.[a-zA-Z]{2,4}|[a-z0-9A-Z]+\.[a-zA-Z]{2,4})$/i", $url)

I just checked this post (after two years). It might be you got the answer, but for those who are beginners, you can use a regular expression to strip every type of URL or query string

(https|http|ftp)\:\/\/|([a-z0-9A-Z]+\.[a-z0-9A-Z]+\.[a-zA-Z]{2,4})|([a-z0-9A-Z]+\.[a-zA-Z]{2,4})|\?([a-zA-Z0-9]+[\&\=\#a-z]+)

It will strip every type of URLs. Take a look at the following list. I used a different type of domains for those who want to ask "will it strip .us, .in, .pk, etc.? type of domains or not.

1. ftp://www.web.com
2. web.net
3. www.website.info
4. website.us
5. web.ws?query=true
6. www.web.biz?query=true
7. ftp://web.in?query=true
8. media.google.com
9. ns.google.pk
10. ww1.smart.au
11. www3.smart.br
12. w1.smart.so
13. ?ques==two&t=p
14. http://website.info?ques==two&t=p
15. https://www.weborwebsite.com

Working Example (tested in PHP5+, Apache2+):

$str = "ftp://www.web.com, web.net, www.website.info, website.us, web.ws?query=true, www.web.biz?query=true, ftp://web.in?query=true, media.google.com hello world, working more with ns ns.google.pk or ww1.smart.au and www3.smart.br w1.smart.so ?ques==two&t=p http://website.info?ques==two&t=p https://www.weborwebsite.com and ftp://www.hotmail.br";
echo preg_replace("/(https|http|ftp)\:\/\/|([a-z0-9A-Z]+\.[a-z0-9A-Z]+\.[a-zA-Z]{2,4})|([a-z0-9A-Z]+\.[a-zA-Z]{2,4})|\?([a-zA-Z0-9]+[\&\=\#a-z]+)/i", "", $str);

it will return

, , , , , , , hello world, working more with ns or and and

This works great for me - including mailto check:

function LinkIt($text)
{
    $t = preg_replace("/(\b(?:(?:http(s)?|ftp):\/\/|(www\.)))([-a-züöäß0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|])/im", '<a target="_blank" href="http$2://$3$4" class="external-link" title="External Link">$1$4</a>', $text);
    return preg_replace("/([\w+\.\-]+@[\w+\-]+\.[a-zA-Z]{2,4})/im", strtolower('<a href="mailto:$1" class="mail" title="E-Mail">$1</a>'), $t);
}

If you want to make that one work, you need to make the "https?//" part optional. Since you seem to have a fairly good grasp of regexps I won't show you. It is an exercise for the reader :)

But I generally agree with Nev. It's overly complicated for what it does.

Use this pattern:

$regex = "(https?\:\/\/|ftp\:\/\/|www\.|[a-z0-9-]+)+([a-z0-9-]+)\.+([a-z]{2,4})((\/|\.)+([a-z0-9-_.\/]*)$|$)";