strcspn

(PHP 4, PHP 5, PHP 7)

strcspn마스크에 매칭하지 않는 처음 세그먼트의 길이를 찾습니다

설명

int strcspn ( string $str1 , string $str2 [, int $start [, int $length ]] )

str1에서 str2 내의 어떠한 문자도 포함하지 않는 첫번째 세그먼트의 길이를 반환합니다.

인수

str1

첫번째 문자열.

str2

두번째 문자열.

start

검사할 문자열의 시작 위치.

length

검사할 문자열의 길이.

반환값

세그먼트의 길이를 정수로 반환합니다.

변경점

버전 설명
4.3.0 startlength 추가

주의

Note: 이 함수는 바이너리 안전입니다.

참고

  • strspn() - 마스크에 매치하는 초기 세그먼트의 길이를 찾는다

add a note add a note

User Contributed Notes 5 notes

up
7
maskedcoder at hotmail dot com
13 years ago
useful for finding beginning of quotes and/or tags in a variable containing html. 
    $pos = strcspn($data, '<"\'');
will find the first occurance of either the beginning of a tag, or a double- or single-quoted string.
up
4
AT-HE (at_he AT hotmai1 DOT com)
13 years ago
this function can be used like strspn(), except while that can be used to compare a string with an allowed pattern, this one can be use to compare a string with a FORBIDDEN pattern

so, to know if any forbidden character has a position inside our string, we can use (not tested with backslashes)...

<?php
// LARGE VERSION
$forbidden="\"\\?*:/@|<>";
if (
strlen($filename) != strcspn($filename,$forbidden)) {
    echo
"you cant create a file with that name!";
}

// SHORT VERSION
if (strlen($filename) - strcspn($filename,"\"\\?*:/@|<>")) {
    echo
"i told you, you cant create that file";
}
?>
up
3
legacyprog at routinz dot net
8 years ago
When you use the third parameter remember that the function will return the number of characters it bypassed, which will *not* be the position in your source string.  It's a simple fix to just add your third parameter value to the function result to get the position in the first string where the scan stopped, but I didn't think of it at first.
up
1
nospam at nospam dot com
2 years ago
It might not be clear from the example, that

strcspn('abcdhelloabcd', 'abcd', -9, -5) == 4

because it's only evaluating 'hell' which doesn't contain any mask, so returns strlen('hell').
up
1
Anonymous
9 years ago
strcspn() can also be thought of as analogous to the following regular expression:
<?php
// where ... represents the mask of characters
preg_match('/[^ ...]/', substr($subject, $start, $length) );
?>
By this analogy, strcspn() can be used in place of some regular expressions to match a pattern without the overhead of a regex engine -- for example, ways to verify if an input string represents a binary value:
<?php
preg_match
('/^[01]+$/i', $subject);
// or...
!preg_match('/[^01]/i', $subject);

// ...or using strcspn()
!strcspn($subject, '01');
?>
To Top