Automaticly replace text with link

gemmini25

Hello

I'm building a site that is heavy on PHP and MySQL and I'm a self learner newcomer so I have some doubts, most I can work out myself others I can search the web for answers with a fair amount of success, others like this one I don't even know how to look for it 🙂

My question is this:

There will be inside a field on a table some entries in the middle of a text like <http://www.example.com Somewhere you should go> and I want php to resolve this text and output something like <a href="http://www.example.com">Somewhere you should go</a>. Of course this text is only is only a stand in and there could be a lot of this kind of entries so it would need to be fully automatic and search the entire text for them.

Thanks in advance

efficacious

I'm afraid I do not understand what you are asking.

PHP is a server side scripting language. It cannot do anything "After the fact"
Meaning. Once the php page is parsed through the php engine. Thats it.

If your talking about reading through another physical file then that is possible and very easy.

You simply need to setup a regular expression to locate your url text and then wrap anchor tags around it.

You abosolutely will need some way of differing between normal text and your special URL text. This will be key to using the regular expression.

Look here for the proper php functions to use for reading through the file.
http://us.php.net/manual/en/ref.filesystem.php

and look here for more info about regexes:
http://us.php.net/manual/en/function.preg-match.php

minorgod

If you're going to build your own function to do this, you'll want to check out preg_replace in the PHP manual as well. You can find many discussons on the topic by searching google for "linkify" or "PHP URLs to Links". However, you may want to look at some existing solutions that "linkify" your user input while protecting you from common exploits in the user input. I highly recommend a PHP library called HTML_Purifier which uses extensive whitelisting rules to clean all your user input. It has a built-in "linkify" function which you can use to automatically convert URLs in the text into HTML links. Also, using HTML_Purifier let's you allow your users to enter normal HTML markup and construct their own links with much less fear of someone exploiting your user input to hack your system or do some kind of scripting attack.