Replace word in a string

[Anon]

Hi!
I'm sure this is a simple question, but I can't figure it out.

I need to replace a word from a string, but it must not affect similar word in another word.

Example:
I would change 'party' to 'meeting' but 'partyfellow' must not be affected.

How to???

I tried
$description = ereg_replace ("$value1", "$value2", $description);

Thanks i advance

[terje-s]

Well, in theory, that's impossible.

If you replace 'party' with 'meeting', ALL instances of 'party' will be replaced (including partyfellow). However, you might want to replace ' party ' with ' meeting '? (note the blanks).

You can use the str_replace() function for this (simpler than the regexp functions, i.e. preg_replace() or ereg_replace()).

Alternately, you can ofcourse explode the string on ' ' compare each element of the array to the string, and replace it on some criteria, then implode() back to a string.

[Anon]

Nah, you want the preg_replace function - it's faster and can recognise word boundaries:

$description = preg_replace("/\b$value1\b/","$value2",$description);

You might want to replace the search and replace texts with arrays, to handle different capitalisations. Just adding an i modifier to the regexp won't cut it, because $value2 would have to be adjusted as well.

$description = preg_replace(
array(
"/\b$value1\b/",
"/\b".strtolower($value1)."\b/",
"/\b".strtoupper($value1)."\b/",
"/\b".ucfirst($value1)."\b/",
"/\b".ucwords($value1)."\b/",
etc...
),array(
"$value2",
strtolower($value2),
strtoupper($value2),
ucfirst($value2),
ucwords($value2),
"$value2",
etc...
)
,$description);

But of course it's a matter of how far you want to go.