(PHP 4, PHP 5, PHP 7, PHP 8)
strcspn — Find length of initial segment not matching mask
Returns the length of the initial segment of
string which does not
contain any of the characters in characters.
If offset and length
are omitted, then all of string will be
examined. If they are included, then the effect will be the same as
calling strcspn(substr($string, $offset, $length),
$characters) (see substr
for more information).
stringThe string to examine.
charactersThe string containing every disallowed character.
offset
The position in string to
start searching.
If offset is given and is non-negative,
then strcspn() will begin
examining string at
the offset'th position. For instance, in
the string 'abcdef', the character at
position 0 is 'a', the
character at position 2 is
'c', and so forth.
If offset is given and is negative,
then strcspn() will begin
examining string at
the offset'th position from the end
of string.
length
The length of the segment from string
to examine.
If length is given and is non-negative,
then string will be examined
for length characters after the starting
position.
If length is given and is negative,
then string will be examined from the
starting position up to length
characters from the end of string.
Returns the length of the initial segment of string
which consists entirely of characters not in characters.
Note:
When a
offsetparameter is set, the returned length is counted starting from this position, not from the beginning ofstring.
| Version | Description |
|---|---|
| 8.4.0 |
Prior to PHP 8.4.0, when characters was the empty string,
the search would incorrectly stop at the first null byte in string.
|
| 8.0.0 |
length is nullable now.
|
Example #1 strcspn() example
<?php
$a = strcspn('banana', 'a');
$b = strcspn('banana', 'abcd');
$c = strcspn('banana', 'z');
$d = strcspn('abcdhelloabcd', 'a', -9);
$e = strcspn('abcdhelloabcd', 'a', -9, -5);
var_dump($a);
var_dump($b);
var_dump($c);
var_dump($d);
var_dump($e);
?>The above example will output:
int(1) int(0) int(6) int(5) int(4)
Note: This function is binary-safe.