PHP Manual: str

Description

mixed str_replace ( mixed search, mixed replace, mixed subject [, int &count] )

This function returns a string or an array with all occurrences of search in subject replaced with the given replace value. If you don't need fancy replacing rules (like regular expressions), you should always use this function instead of ereg_replace() or preg_replace().

As of PHP 4.0.5, every parameter in str_replace() can be an array.

Warning

In PHP versions prior to 4.3.3 a bug existed when using arrays as both search and replace parameters which caused empty search indexes to be skipped without advancing the internal pointer on the replace array. This has been corrected in PHP 4.3.3, any scripts which relied on this bug should remove empty search values prior to calling this function in order to mimick the original behavior.

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.

If search and replace are arrays, then str_replace() takes a value from each array and uses them to do 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.

Example 1. str_replace() examples

<?php
// Provides: <body text='black'>
$bodytag = str_replace("%body%", "black", "<body text='%body%'>");

// Provides: Hll Wrld f PHP
$vowels = array("a", "e", "i", "o", "u", "A", "E", "I", "O", "U");
$onlyconsonants = str_replace($vowels, "", "Hello World of PHP");

// Provides: You should eat pizza, beer, and ice cream every day
$phrase  = "You should eat fruits, vegetables, and fiber every day.";
$healthy = array("fruits", "vegetables", "fiber");
$yummy   = array("pizza", "beer", "ice cream");

$newphrase = str_replace($healthy, $yummy, $phrase);

// Use of the count parameter is available as of PHP 5.0.0
$str = str_replace("ll", "", "good golly miss molly!", $count);
echo $count; // 2
?>

Note: This function is binary-safe.

Note: As of PHP 5.0.0 the number of matched and replaced needles (search) will be returned in count which is passed by reference. Prior to PHP 5.0.0 this parameter is not available.