highlighting individual words in strings

pablodelapena

had a wee search on the forums but found nothing of any use.

What I want to do is find words within a string and highlight them as a block of colour.

I'm using this for a search facility and can do ti no problem with str_replace(), however if the search contains more than oneword it begins to be a problem as it will not highlight individual words but the 2 words and then only if they are together.

Any help at how I cna have PHP take a string apart and then search through a string replacing the word?

AstroTeg

I'm thinking the easiest way might be to loop that str_replace() function for each word you find in the search query. Use explode(' ', $var) to break out each individual word in the search and then loop that many times. Shouldn't be difficult and you shouldn't have to change too much code (in theory).

suntra

I suggest you use explode(), then you highlight each word contained in the array...

<?
$strTexte = 'My name\\'s Suntra. I\\'m a dog and I like life as much as a cat.';
// « ' » should be escaped. The forum removes any backslashes I add...
$strMots = 'my life as a dog';
$arrMots = explode(' ', $strMots);
$strColDebut = '<SPAN STYLE="background-color:#FF0000;">';
$strColFin = '</SPAN>';
foreach($arrMots as $strValeur) {
   $strTexte = str_replace($strValeur, $strColDebut . $strValeur . $strColFin, $strTexte);
}
?>

Notice : code was not tested !

pablodelapena

awesome! thanks guys! 🙂

suntra

If you use PHP 5, and ONLY Php 5, you can also use str_ireplace(). It will replace a word without caring about the case...

Example :

echo str_replace("allo", "salut", "ALLO");
... will return "ALLO" and not "salut"

echo str_ireplace("allo", "salut", "ALLO");
... will return "salut", that's what we want !

But remember... only PHP 5 !

If, like me, you don't have PHP 5, you can use eregi_replace()... !

Weedpacket

with preg_replace(), you could match

"/\b(word)\b/i" and replace it with "<span style='background-color:red'>$1</span>"

That will accommodate upper- and lowercase, and will also prevent parts of words being mishighlighted if they happen to be other words.

Note that preg_replace() can take arrays for its first two arguments, and so by building suitable arrays in advance, all of the replacements can be carried out with just one preg_replace() call.