strtok
(PHP 4, PHP 5, PHP 7, PHP 8)
strtok — Tokenize string
Description
$string, string $token): string|falseAlternative signature (not supported with named arguments):
$token): string|false
strtok() splits a string (string)
into smaller strings (tokens), with each token being delimited by any
character from token.
That is, if you have a string like "This is an example string" you
could tokenize this string into its individual words by using the
space character as the token.
Note that only the first call to strtok uses the string argument.
Every subsequent call to strtok only needs the token to use, as
it keeps track of where it is in the current string. To start
over, or to tokenize a new string you simply call strtok with the
string argument again to initialize it. Note that you may put
multiple tokens in the token parameter. The string will be
tokenized when any one of the characters in the token argument is
found.
Note:
This function behaves slightly different from what one may expect being familiar with explode(). First, a sequence of two or more contiguous
tokencharacters in the parsed string is considered to be a single delimiter. Also, atokensituated at the start or end of the string is ignored. For example, if a string";aaa;;bbb;"is used, successive calls to strtok() with";"as atokenwould return strings "aaa" and "bbb", and thenfalse. As a result, the string will be split into only two elements, whileexplode(";", $string)would return an array of 5 elements.
Parameters
-
string -
The string being split up into smaller strings (tokens).
-
token -
The delimiter used when splitting up
string.
Return Values
A string token, or false if no more tokens are available.
Examples
Example #1 strtok() example
<?php
$string = "This is\tan example\nstring";
/* Use tab and newline as tokenizing characters as well */
$tok = strtok($string, " \n\t");
while ($tok !== false) {
echo "Word=$tok<br />";
$tok = strtok(" \n\t");
}
?>
Example #2 strtok() behavior on empty part found
<?php
$first_token = strtok('/something', '/');
$second_token = strtok('/');
var_dump($first_token, $second_token);
?>
The above example will output:
string(9) "something"
bool(false)
Example #3 The difference between strtok() and explode()
<?php
$string = ";aaa;;bbb;";
$parts = [];
$tok = strtok($string, ";");
while ($tok !== false) {
$parts[] = $tok;
$tok = strtok(";");
}
echo json_encode($parts),"\n";
$parts = explode(";", $string);
echo json_encode($parts),"\n";
The above example will output:
["aaa","bbb"] ["","aaa","","bbb",""]
Notes
This function may
return Boolean false, but may also return a non-Boolean value which
evaluates to false. Please read the section on Booleans for more
information. Use the ===
operator for testing the return value of this
function.
