(PHP 4, PHP 5, PHP 7, PHP 8)
strrpos — Find the position of the last occurrence of a substring in a string
$haystack, string $needle, int $offset = 0): int|false
Find the numeric position of the last occurrence of
needle in the haystack string.
haystackThe string to search in.
needle
Prior to PHP 8.0.0, if needle is not a string, it is converted
to an integer and applied as the ordinal value of a character.
This behavior is deprecated as of PHP 7.3.0, and relying on it is highly
discouraged. Depending on the intended behavior, the
needle should either be explicitly cast to string,
or an explicit call to chr() should be performed.
offset
If zero or positive, the search is performed left to right skipping the
first offset bytes of the
haystack.
If negative, the search is performed right to left skipping the
last offset bytes of the
haystack and searching for the first occurrence
of needle.
Note:
This is effectively looking for the last occurrence of
needlebefore the lastoffsetbytes.
Returns the position where the needle exists relative to the beginning of
the haystack string (independent of search direction
or offset).
Note: String positions start at 0, and not 1.
Returns false if the needle was not found.
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 ===
operator for testing the return value of this
function.
| Version | Description |
|---|---|
| 8.0.0 |
Passing an int as needle is no longer supported.
|
| 7.3.0 |
Passing an int as needle has been deprecated.
|
Example #1 Checking if a needle is in the haystack
It is easy to mistake the return values for "character found at position 0" and "character not found". Here's how to detect the difference:
<?php
$pos = strrpos($mystring, "b");
if ($pos === false) { // note: three equal signs
// not found...
}
?>
Example #2 Searching with offsets
<?php
$foo = "0123456789a123456789b123456789c";
// Looking for '0' from the 0th byte (from the beginning)
var_dump(strrpos($foo, '0', 0));
// Looking for '0' from the 1st byte (after byte "0")
var_dump(strrpos($foo, '0', 1));
// Looking for '7' from the 21th byte (after byte 20)
var_dump(strrpos($foo, '7', 20));
// Looking for '7' from the 29th byte (after byte 28)
var_dump(strrpos($foo, '7', 28));
// Looking for '7' right to left from the 5th byte from the end
var_dump(strrpos($foo, '7', -5));
// Looking for 'c' right to left from the 2nd byte from the end
var_dump(strrpos($foo, 'c', -2));
// Looking for '9c' right to left from the 2nd byte from the end
var_dump(strrpos($foo, '9c', -2));
?>
The above example will output:
int(0) bool(false) int(27) bool(false) int(17) bool(false) int(29)