preg_replace just the first occurance

[joshjryan]

I need to do a preg_replace but I only want it to replace the first occurrence, not everything that matches the regular expression in my string.
I know that there is the ability to store the count to the variable, but since the function does not loop to do its replacements, that doesn't help.
If anyone knows how to do that with str_replace too, that would work.
Thanks,
Josh

[nrg_alpha]

Show samples of what you are looking to replace and with what you want to replace with.. If what you are looking to find and replace is straight foward (i.e, no regex required), then yes, str_replace is advisable (as this does have a count parameter that can be used for a single instance if I'm not mistaken)... not sure what you mean by counting variables and non-loops, I can't quite understand what you are talking about there without code samples...

[joshjryan]

foreach ($original as $key=>$value) {
	$string = str_replace($value, $replace[$key], $string);
}

I am using preg_match_all to get an array of matched items then I am looping through that to find what it should be replaced with. Those are then stored into two arrays ($original and $replace).
So I want to find $original[$key] in $string and replace it with $replace[$key], in a loop.
So by the end of the loop, I will have replaced all the items in $string that were found in my original RegEx.
Thanks for your help!

[joshjryan]

I have been looking around all night and just found something on bugs.php.net:

function str_replaceFirst($s,$r,$str)
{
	$l = strlen($str);
	$a = strpos($str,$s);
	$b = $a + strlen($s);
	$temp = substr($str,0,$a) . $r . substr($str,$b,($l-$b));
	return $temp;
}

this does what i was looking for.
Thanks for your help!

[NogDog]

[man]preg_replace/man has an optional "limit" argument you could set to one so that it only replaces the first occurrence.