(PHP 4, PHP 5)
str_replace — Replace all occurrences of the search string with the replacement string
$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 givenreplace
value.
If you don't need fancy replacing rules (like regular expressions), you should always use this function instead ofpreg_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.
count
parameter
was added.
4.3.3
The behaviour of this function changed. In older versions a bug existed when using arrays as bothsearch
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
// Provides:
$bodytag = str_replace("%body%", "black", "");
// 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
// Order of replacement
$str = "Line 1\nLine 2\rLine 3\r\nLine 4\n";
$order = array("\r\n", "\n", "\r");
$replace = '
';
// 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.