Replace every other occurrence with str_replace
Well, someone put some code onto the str_replace PHP manual page to replace every other occurrence of a string with another string. However, it didn’t work, and was simply spam to get a link onto the PHP manual page (shame on them). So I made a function that DID work, for the poor lost souls who would be trying over and over to make that one work. I figured that since I made it, I might as well post it, maybe someone needs something like this.
/**
* Replaces every other occurrence of search in haystack with replace
*
* @param $needle mixed
* @param $replace mixed
* @param $haystack mixed
* @param $count int[optional]
* @param $replace_first bool[optional] - Default true
* @return mixed
*/
function str_replace_every_other($needle, $replace, $haystack, &$count=null, $replace_first=true) {
$count = 0;
$offset = strpos($haystack, $needle);
//If we don't replace the first, go ahead and skip it
if (!$replace_first) {
$offset += strlen($needle);
$offset = strpos($haystack, $needle, $offset);
}
while ($offset !== false) {
$haystack = substr_replace($haystack, $replace, $offset, strlen($needle));
$count++;
$offset += strlen($replace);
$offset = strpos($haystack, $needle, $offset);
if ($offset !== false) {
$offset += strlen($needle);
$offset = strpos($haystack, $needle, $offset);
}
}
return $haystack;
}
//Use it like this:
$str = "one two one two one two";
echo str_replace_every_other('one', 'two', $str, $count).'\r\n';
//two two one two two two
echo str_replace_every_other('one', 'two', $str, $count, false).'\r\n';
//one two two two one two
I added the last option ($replace_first) to let you replace the odd occurrences (true, default) or the evens (false).
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Aaron is the man behind the curtain here at Xavisys. He gets things done and really knows his way around the code.
Well, it’s not real easy with that function, but basically, when you see $offset = strpos(…), that’s skipping some space in the string. You should be able to duplicate those commands.
Your site is very useful for me to do many steps.
Your str_replace_every_other() function just saved me hours of time! I used it to take over 1000 lines of sorted table data and build it into a multidimensional array.
I’m on an apache server, and it rejected your str_replace_every_other() function the first time I ran it, because of the equal signs in the optional parameters. I simply changed the “&$count=null, $replace_first=true” to “$count, $replace_first” and made sure to supply the parameters. After the change, I received the result I was looking for. So, if you’re encountering the same problem, that’s the solution that worked for me.
Thanks Aaron!