Find the position of the first occurrence of a case-insensitive substring in a string
Syntax
stripos(string $haystack, string $needle, int $offset = 0): int|false
Parameters
haystack
The string to search.
needle
The string to find.
The needle should either be explicitly cast to string, or an explicit call to chr() should be performed.
offset
If specified, search will start this number of characters counted from the beginning of the string. If the offset is negative, the search will start this number of characters counted from the end of the string.
Return
Returns the position of where the needle exists relative to the beginnning of the haystack string (independent of offset). Also note that string positions start at 0, and not 1. Returns FALSE if the needle was not found.
Warning: This function may return Boolean FALSE, but may also return a non-Boolean value which evaluates to FALSE. Please read the section on Booleans for more information. Use the identity operator (===) for testing the return value of this function.
Examples
1 · haystack needle · string
<? $haystack = 'CASEcase'; $needle = 's'; $return = stripos($haystack, $needle); echo $return; ?>
2
2 · haystack needle · chr
<? $haystack = 'CASEcase'; $needle = chr(115); $return = stripos($haystack, $needle); echo $return; ?>
2
3 · offset · Negative
<? $haystack = 'CASEcase'; $needle = 's'; $offset = -4; $return = stripos($haystack, $needle, $offset); echo $return; ?>
6
4 · offset · Non-negative
<? $haystack = 'CASEcase'; $needle = 's'; $offset = 4; $return = stripos($haystack, $needle, $offset); echo $return; ?>
6
5 · Return
<? // use identity operator (===) instead of comparison operator (==) to test return $haystack = 'abc'; $needle = 'a'; $return = stripos($haystack, $needle); if($return === false) { echo "not found"; } else { echo "found"; } ?>
found