(PHP 4, PHP 5, PHP 7)
strpos — Find the position of the first occurrence of a substring in a string
strpos ( string $haystack , string $needle [, int $offset = 0 ] ) : int|false
Find the numeric position of the first occurrence of needle in the haystack string.
haystack
The 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 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.
Returns the position of where the needle exists relative to the beginning 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.
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. |
| 7.1.0 | Support for negative offsets has been added. |
Example #1 Using ===
<?php
$mystring = 'abc';
$findme = 'a';
$pos = strpos($mystring, $findme);
// Note our use of ===. Simply == would not work as expected
// because the position of 'a' was the 0th (first) character.
if ($pos === false) {
echo "The string '$findme' was not found in the string '$mystring'";
} else {
echo "The string '$findme' was found in the string '$mystring'";
echo " and exists at position $pos";
}
?> Example #2 Using !==
<?php
$mystring = 'abc';
$findme = 'a';
$pos = strpos($mystring, $findme);
// The !== operator can also be used. Using != would not work as expected
// because the position of 'a' is 0. The statement (0 != false) evaluates
// to false.
if ($pos !== false) {
echo "The string '$findme' was found in the string '$mystring'";
echo " and exists at position $pos";
} else {
echo "The string '$findme' was not found in the string '$mystring'";
}
?> Example #3 Using an offset
<?php // We can search for the character, ignoring anything before the offset $newstring = 'abcdef abcdef'; $pos = strpos($newstring, 'a', 1); // $pos = 7, not 0 ?>
Note: This function is binary-safe.
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.strpos.php