PHP: Replace all occurrences of the search string with the replacement string

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().

Parameters

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.

If search or replace are arrays, their elements are processed first to last.

search
replace
subject: 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.
count: Note: If passed, this will hold the number of matched and replaced needles.

Return Values

This function returns a string or an array with the replaced values.

ChangeLog

Version Description

5.0.0 The count parameter was added.

4.3.3 The behaviour of this function changed. In older versions 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 mimic the original behavior.

4.0.5 Most parameters can now be an array.

Examples

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



// Order of replacement

$str     = "Line 1\nLine 2\rLine 3\r\nLine 4\n";

$order   = array("\r\n", "\n", "\r");

$replace = '<br />';

// Processes \r\n's first so they aren't converted twice.

$newstr = str_replace($order, $replace, $str);



// Outputs: apearpearle pear

$letters = array('a', 'p');

$fruit   = array('apple', 'pear');

$text    = 'a p';

$output  = str_replace($letters, $fruit, $text);

echo $output;

?>

Notes

Note: This function is binary-safe.

Note: This function is case-sensitive. Use str_ireplace() for case-insensitive replace.

str_replace