strspn
(PHP 4, PHP 5)
strspn — Finds the length of the first segment of a string consisting entirely of characters contained within a given mask.
Description
Returns the length of the first group of consecutive characters from mask found in subject.
If start and length are omitted, then all of subject will be examined. If they are included, then the effect will be the same as calling strspn(substr($subject, $start, $length), $mask) (see substr for more information).
The line of code:
<?php
$var = strspn("42 is the answer to the 128th question.", "1234567890");
?>
Parameters
- subject
-
The string to examine.
- mask
-
The list of allowable characters to include in counted segments.
- start
-
The position in subject to start searching.
If start is given and is non-negative, then strspn() will begin examining subject at the start'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 start is given and is negative, then strspn() will begin examining subject at the start'th position from the end of subject.
- length
-
The length of the segment from subject to examine.
If length is given and is non-negative, then subject will be examined for length characters after the starting position.
If lengthis given and is negative, then subject will be examined from the starting position up to length characters from the end of subject.
Return Values
Returns the length of the initial segment of str1 which consists entirely of characters in str2.
Changelog
| Version | Description |
|---|---|
| 4.3.0 | The start and length parameters were added |
Examples
Example #1 strspn() example
<?php
echo strspn("foo", "o", 1, 2); // prints: 2
?>
Notes
Note: This function is binary-safe.