(PHP 4, PHP 5)
str_replace — Replace all occurrences of the search string with the replacement string
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().
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.
This function returns a string or an array with the replaced values.
| 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. |
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;
?>
Note: This function is binary-safe.
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.