(PHP 4, PHP 5)
strspn — Finds the length of the initial segment of a string consisting entirely of characters contained within a given mask.
Finds the length of the initial segment of
subject that contains only characters from
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:
$var = strspn("42 is the answer to the 128th question.", "1234567890");
subjectthat consists only of characters contained within "1234567890".
The string to examine.
The list of allowable characters.
The position in
subject to start searching.
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.
start is given and is negative, then strspn() will begin examining
subject at the
start'th position from the end of
The length of the segment from
subject to examine.
length is given and is non-negative, then
subject will be examined for
length characters after the starting position.
lengthis given and is negative, then
subject will be examined from the starting position up to
length characters from the end of
Returns the length of the initial segment of
subject which consists entirely of characters in
|4.3.0|| The |
Example #1 strspn() example
// subject does not start with any characters from mask
// examine two characters from subject starting at offset 1
var_dump(strspn("foo", "o", 1, 2));
// examine one character from subject starting at offset 1
var_dump(strspn("foo", "o", 1, 1));
The above example will output:
int(0) int(2) int(1)
Note: This function is binary-safe.