stristr

(PHP 4, PHP 5, PHP 7, PHP 8)

stristr — Case-insensitive strstr()

Description

function stristr(string $haystack, string $needle, bool $before_needle = false): string|false

Returns all of haystack starting from and including the first occurrence of needle to the end.

Parameters

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.
before_needle

If true, stristr() returns the part of the haystack before the first occurrence of the needle (excluding needle).

needle and haystack are examined in a case-insensitive manner.

Return Values

Returns the matched substring. If needle is not found, returns false.

Changelog

Version Description
8.2.0 Case folding no longer depends on the locale set with setlocale(). Only ASCII case folding will be done. Non-ASCII bytes will be compared by their byte value.
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.

Examples

Example #1 stristr() example

<?php
  $email = 'USER@EXAMPLE.com';
  echo stristr($email, 'e'), PHP_EOL; // outputs ER@EXAMPLE.com
  echo stristr($email, 'e', true), PHP_EOL; // outputs US
?>

Example #2 Testing if a string is found or not

<?php
  $string = 'Hello World!';
  if (stristr($string, 'earth') === FALSE) {
    echo '"earth" not found in string';
  }
// outputs: "earth" not found in string
?>

Notes

Note: This function is binary-safe.

See Also

  • strstr() - Find the first occurrence of a string
  • strrchr() - Find the last occurrence of a character in a string
  • stripos() - Find the position of the first occurrence of a case-insensitive substring in a string
  • strpbrk() - Search a string for any of a set of characters
  • preg_match() - Perform a regular expression match

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User Contributed Notes 5 notes

up
18
dpatton.at.confluence.org
23 years ago
There was a change in PHP 4.2.3 that can cause a warning message
to be generated when using stristr(), even though no message was
generated in older versions of PHP.

The following will generate a warning message in 4.0.6 and 4.2.3:
  stristr("haystack", "");
     OR
  $needle = "";  stristr("haystack", $needle);

This will _not_ generate an "Empty Delimiter" warning message in
4.0.6, but _will_ in 4.2.3:
  unset($needle); stristr("haystack", $needle);

Here's a URL that documents what was changed:
http://groups.google.ca/groups?selm=cvshholzgra1031224321%40cvsserver
up
7
giz at gbdesign dot net
18 years ago
Just been caught out by stristr trying to converting the needle from an Int to an ASCII value.

Got round this by casting the value to a string.

<?php
if( !stristr( $file, (string) $myCustomer->getCustomerID()  ) ) {
  // Permission denied
}
?>
up
3
Techdeck at Techdeck dot org
23 years ago
An example for the stristr() function:

<?php
$a = "I like php";
if (stristr("$a", "LikE PhP")) {
print ("According to \$a, you like PHP.");
}
?>

It will look in $a for "like php" (NOT case sensetive. though, strstr() is case-sensetive).

For the ones of you who uses linux.. It is similiar to the "grep" command.
Actually.. "grep -i".
up
0
notepad at codewalkers dot com
21 years ago
<?php

function stristr_reverse($haystack, $needle) {
  $pos = stripos($haystack, $needle) + strlen($needle);
  return substr($haystack, 0, $pos);
}
$email = 'USER@EXAMPLE.com';
echo stristr_reverse($email, 'er');
// outputs USER

?>
up
-3
jukka
12 years ago
I think there is a bug in php 5.3 in stristr with uppercase Ä containing other character

http://pastebin.com/5bP6uztY

if you search only with täry it works, but as soon as the word is tärylä  it does not. TÄRYL works fine
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