str_repeat
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String Functions
PHP Manual

# str_replace

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 preg_replace.

### Parameters

If `search` and `replace` are arrays, then str_replace 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.

`search`

  The value being searched for, otherwise known as the needle. An array may be used to designate multiple needles.

`replace`

  The replacement value that replaces found `search` values. An array may be used to designate multiple replacements.

`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.

`count`

  If passed, this will be set to the number of replacements performed.

### 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 Basic 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);
// Provides: 2
$str = str_replace("ll", "", "good golly miss molly!", $count);
echo $count;
?>`

Example #2 Examples of potential str_replace gotchas

`<?php
// 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 F because A is replaced with B, then B is replaced with C, and so on...
// Finally E is replaced with F, because of left to right replacements.
$search = array('A', 'B', 'C', 'D', 'E');
$replace = array('B', 'C', 'D', 'E', 'F');
$subject = 'A';
echo str_replace($search, $replace, $subject);
// Outputs: apearpearle pear
// For the same reason mentioned above
$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.

Caution

# Replacement order gotcha

Because str_replace replaces left to right, it might replace a previously inserted value when doing multiple replacements. See also the examples in this document.

> Note:

> This function is case-sensitive. Use str_ireplace for case-insensitive replace.

### See Also

- str_ireplace
- substr_replace
- preg_replace
- strtr