str_contains

(PHP 8)

str_containsDetermine if a string contains a given substring

Description

str_contains(string $haystack, string $needle): bool

Performs a case-sensitive check indicating if needle is contained in haystack.

Parameters

haystack

The string to search in.

needle

The substring to search for in the haystack.

Return Values

Returns true if needle is in haystack, false otherwise.

Examples

Example #1 Using the empty string ''

<?php
if (str_contains('abc''')) {
    echo 
"Checking the existence of the empty string will always return true";
}
?>

The above example will output:

Checking the existence of the empty string will always return true

Example #2 Showing case-sensitivity

<?php
$string 
'The lazy fox jumped over the fence';

if (
str_contains($string'lazy')) {
    echo 
"The string 'lazy' was found in the string\n";
}

if (
str_contains($string'Lazy')) {
    echo 
'The string "Lazy" was found in the string';
} else {
    echo 
'"Lazy" was not found because the case does not match';
}

?>

The above example will output:

The string 'lazy' was found in the string
"Lazy" was not found because the case does not match

Notes

Note: This function is binary-safe.

See Also

  • str_ends_with() - Checks if a string ends with a given substring
  • str_starts_with() - Checks if a string starts with a given substring
  • stripos() - Find the position of the first occurrence of a case-insensitive substring in a string
  • strrpos() - Find the position of the last occurrence of a substring in a string
  • strripos() - Find the position of the last occurrence of a case-insensitive substring in a string
  • strstr() - Find the first occurrence of a string
  • strpbrk() - Search a string for any of a set of characters
  • substr() - Return part of a string
  • preg_match() - Perform a regular expression match

add a note

User Contributed Notes 7 notes

up
65
scm6079
1 year ago
For earlier versions of PHP, you can polyfill the str_contains function using the following snippet:

<?php
// based on original work from the PHP Laravel framework
if (!function_exists('str_contains')) {
    function
str_contains($haystack, $needle) {
        return
$needle !== '' && mb_strpos($haystack, $needle) !== false;
    }
}
?>
up
2
aisunny7 dot xy at gmail dot com
8 months ago
The polyfill that based on original work from the PHP Laravel framework had a different behavior;

when the $needle is `""` or `null`:
php8's will return `true`;
but, laravel'str_contains will return `false`;

when php8.1, null is deprecated, You can use `$needle ?: ""`;
up
4
juliyvchirkov at gmail dot com
1 year ago
<?php

// Polyfill for PHP 4 - PHP 7, safe to utilize with PHP 8

if (!function_exists('str_contains')) {
    function
str_contains (string $haystack, string $needle)
    {
        return empty(
$needle) || strpos($haystack, $needle) !== false;
    }
}
up
2
drupalista dot com dot br at gmail dot com
5 months ago
private function contains(array $needles, string $type, string $haystack = NULL, string $filename = NULL) : bool {
        if (empty($needles)) return FALSE;
        if ($filename)
            $haystack = file_get_contents($filename);

        $now_what = function(string $needle) use ($haystack, $type) : array {
            $has_needle = str_contains($haystack, $needle);
            if ($type === 'any' && $has_needle)
                return ['done' => TRUE, 'return' => TRUE];

            if ($type === 'all' && !$has_needle)
                return ['done' => TRUE, 'return' => FALSE];

            return ['done' => FALSE];
        };

        foreach ($needles as $needle) {
            $check = $now_what($needle);
            if ($check['done'])
                return $check['return'];
        }
        return TRUE;
    }

    function containsAny(array $needles, string $haystack = NULL, string $filename = NULL) : bool {
        return self::contains($needles, 'any', $haystack, $filename);
    }

    function containsAll(array $needles, string $haystack = NULL, string $filename = NULL) : bool {
        return self::contains($needles, 'all', $haystack, $filename);
    }
up
1
olivertasche+nospam at gmail dot com
1 year ago
The code from "me at daz dot co dot uk" will not work if the word is
- at the start of the string
- at the end of the string
- at the end of a sentence (like "the ox." or "is that an ox?")
- in quotes
- and so on.

You should explode the string by whitespace, punctations, ... and check if the resulting array contains your word OR try to test with a RegEx like this:
(^|[\s\W])+word($|[\s\W])+

Disclaimer: The RegEx may need some tweaks
up
-5
AuxData
10 months ago
Until PHP 8 was released, many-a-programmer were writing our own contain() functions. Mine also handles needles with logical ORs (set to '||').
Here it is.

function contains($haystack, $needle, $offset){
    $OR = '||';
    $result = false;
   
    $ORpos = strpos($needle, $OR, 0);
    if($ORpos !== false){ //ORs exist in the needle string
        $needle_arr = explode($OR, $needle);
        for($i=0; $i < count($needle_arr); $i++){
            $pos = strpos($haystack, trim($needle_arr[$i]), $offset);
            if($pos !== false){
                $result = true;
                break;
            }
        }       
    } else {
        $pos = strpos($haystack, trim($needle), $offset);
        if($pos !== false){
          $result = true;
        }
    }
  return($result);
}

Call: contains("Apple Orange Banana", "Apple || Walnut", 0);
Returns: true
up
-33
kadenskinner at gmail dot com
1 year ago
<?php

$needle
= '@';
$haystack = 'user@example.com';

if (!
str_contains($haystack, $needle)){
echo
'There is not an @ in haystack';
}else{
echo
'There is an @ in haystack';
}
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