(PHP 4, PHP 5, PHP 7, PHP 8)
strrpos — Find the position of the last occurrence of a substring in a string
Find the numeric position of the last occurrence of
needle
in the haystack
string.
haystack
The string to search in.
needle
The string to search for.
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 starts offset
bytes from
the right instead of from the beginning of haystack
.
The search is performed right to left, searching for the first
occurrence of needle
from the selected byte.
Note:
This is effectively looking for the last occurrence of
needle
at or before the lastoffset
bytes.
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 |
needle now accepts an empty string.
|
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)