preg_filter(3) [php man page]
PREG_FILTER(3) 1 PREG_FILTER(3) preg_filter - Perform a regular expression search and replace SYNOPSIS
mixed preg_filter (mixed $pattern, mixed $replacement, mixed $subject, [int $limit = -1], [int &$count]) DESCRIPTION
preg_filter(3) is identical to preg_replace(3) except it only returns the (possibly transformed) subjects where there was a match. For details about how this function works, read the preg_replace(3) documentation. RETURN VALUES
Returns an array if the $subject parameter is an array, or a string otherwise. If no matches are found or an error occurred, an empty array is returned when $subject is an array or NULL otherwise. EXAMPLES
Example #1 Example comparing preg_filter(3) with preg_replace(3) <?php $subject = array('1', 'a', '2', 'b', '3', 'A', 'B', '4'); $pattern = array('/d/', '/[a-z]/', '/[1a]/'); $replace = array('A:$0', 'B:$0', 'C:$0'); echo "preg_filter returns "; print_r(preg_filter($pattern, $replace, $subject)); echo "preg_replace returns "; print_r(preg_replace($pattern, $replace, $subject)); ?> The above example will output: preg_filter returns Array ( [0] => A:C:1 [1] => B:C:a [2] => A:2 [3] => B:b [4] => A:3 [7] => A:4 ) preg_replace returns Array ( [0] => A:C:1 [1] => B:C:a [2] => A:2 [3] => B:b [4] => A:3 [5] => A [6] => B [7] => A:4 ) SEE ALSO
PCRE Patterns, preg_quote(3), preg_replace(3), preg_replace_callback(3), preg_grep(3), preg_last_error(3). PHP Documentation Group PREG_FILTER(3)
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STR_IREPLACE(3) 1 STR_IREPLACE(3) str_ireplace - Case-insensitive version ofstr_replace(3). SYNOPSIS
mixed str_ireplace (mixed $search, mixed $replace, mixed $subject, [int &$count]) DESCRIPTION
This function returns a string or an array with all occurrences of $search in $subject (ignoring case) replaced with the given $replace value. If you don't need fancy replacing rules, you should generally use this function instead of preg_replace(3) with the i modifier. PARAMETERS
If $search and $replace are arrays, then str_ireplace(3) takes a value from each array and uses them to search and replace on $subject. If $replace has fewer values than $search, then an empty string is used for the rest of replacement values. If $search is an array and $replace is a string, then this replacement string is used for every value of $search. The converse would not make sense, though. If $search or $replace are arrays, their elements are processed first to last. o $search - The value being searched for, otherwise known as the needle. An array may be used to designate multiple needles. o $replace - The replacement value that replaces found $search values. An array may be used to designate multiple replacements. o $subject - The string or array being searched and replaced on, otherwise known as the haystack. If $subject is an array, then the search and replace is performed with every entry of $subject, and the return value is an array as well. o $count - If passed, this will be set to the number of replacements performed. RETURN VALUES
Returns a string or an array of replacements. EXAMPLES
Example #1 str_ireplace(3) example <?php $bodytag = str_ireplace("%body%", "black", "<body text=%BODY%>"); ?> NOTES
Note This function is binary-safe. Caution Replacement order gotcha Because str_ireplace(3) replaces left to right, it might replace a previously inserted value when doing multiple replacements. Example #2 in the str_replace(3) documentation demonstrates how this may affect you in practice. SEE ALSO
str_replace(3), preg_replace(3), strtr(3). PHP Documentation Group STR_IREPLACE(3)