strspn() - string

Finds the length of the initial segment of subject
   that contains only characters from mask.

Parameters : 
 subject - The string to examine. 
 mask - The list of allowable characters. 
 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 length is given and is negative,
        then subject will be examined from the
        starting position up to length
        characters from the end of subject. 

Syntax

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

Example

<?php$var = strspn("42 is the answer to the 128th question.", "1234567890");?>

Output / Return Value

Limitations

Alternatives / See Also

Reference