String Functions
PHP Manual

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

int strspn ( string $subject , string $mask [, int $start [, int $length ]] )

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");
?>
will assign 2 to $var, because the string "42" is the first segment from subject to consist only of characters contained within "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"12); // prints: 2
?>

Notes

Note: This function is binary-safe.

See Also


String Functions
PHP Manual