How can I check if a word is contained in another string using PHP?

Question

Pseudo Code

text = "I go to school";
word = "to"
if ( word.exist(text) ) {
    return true ;
else {
    return false ;
}

I am looking for a PHP function which returns true if the word exists in the text.

possible duplicate of [How to check if a string contains specific words?](http://stackoverflow.com/questions/4366730/how-to-check-if-a-string-contains-specific-words) — mawburn, Jul 17 '14 at 23:50
You might find [`s($text)->contains($word)`](https://github.com/delight-im/PHP-Str/blob/8fd0c608d5496d43adaa899642c1cce047e076dc/src/Str.php#L93) or [`s($text)->containsIgnoreCase($word)`](https://github.com/delight-im/PHP-Str/blob/8fd0c608d5496d43adaa899642c1cce047e076dc/src/Str.php#L105) helpful, as found in [this standalone library](https://github.com/delight-im/PHP-Str). — caw, Jul 27 '16 at 00:24

score 116 · Accepted Answer · edited Nov 27 '20 at 00:32

You have a few options depending on your needs. For this simple example, strpos() is probably the simplest and most direct function to use. If you need to do something with the result, you may prefer strstr() or preg_match(). If you need to use a complex pattern instead of a string as your needle, you'll want preg_match().

$needle = "to";
$haystack = "I go to school";

strpos() and stripos() method (stripos() is case insensitive):

if (strpos($haystack, $needle) !== false) echo "Found!";

strstr() and stristr() method (stristr is case insensitive):

if (strstr($haystack, $needle)) echo "Found!";

preg_match method (regular expressions, much more flexible but runs slower):

if (preg_match("/to/", $haystack)) echo "Found!";

Because you asked for a complete function, this is how you'd put that together (with default values for needle and haystack):

function match_my_string($needle = 'to', $haystack = 'I go to school') {
  if (strpos($haystack, $needle) !== false) return true;
  else return false;
}

PHP 8.0.0 now contains a str_contains function that works like so:

if (str_contains($haystack, $needle)) {
    echo "Found";
}

Non php'ers (like myself) note the double-equals in `!== false` because strpos() may return 0 if a match is found right at the beginning of the string (character position zero). — Josh, Nov 28 '13 at 13:36
couldn't you just do `return (strpos($haystack, $needle) !== false);`? It has the exact same result, just a cleaner code — Nico, Nov 12 '14 at 13:37

score 21 · Answer 2 · answered Jun 19 '09 at 22:52

21

function hasWord($word, $txt) {
    $patt = "/(?:^|[^a-zA-Z])" . preg_quote($word, '/') . "(?:$|[^a-zA-Z])/i";
    return preg_match($patt, $txt);
}

If $word is "to", this will match:

"Listen to Me"
"To the moon"
"up-to-the-minute"

but not:

"Together"
"Into space"

answered Jun 19 '09 at 22:52

Steve Clay

8,671
2
42
48

perfect solution, though of course accepted answer is correct as per the question asked – hi0001234d Apr 28 '16 at 16:23
Perfect solution, as strpos() returns true even if it matches a part of string instead of whole word. Example: $haystack="check that fork"; $needle="for"; Now in this case, strpos() will find a match and return true. But peg_match() won't find 'for' word in the haystack, it will return 0. – Saket Sep 23 '20 at 19:35

score 15 · Answer 3 · edited Jun 19 '09 at 17:58

15

use:

return (strpos($text,$word) !== false); //case-sensitive

or

return (stripos($text,$word) !== false); //case-insensitive

edited Jun 19 '09 at 17:58

Itay Moav -Malimovka

52,579
61
190
278

answered Jun 19 '09 at 17:46

Jonathan Fingland

56,385
11
85
79

You got'em backwards. stripos is case-insensitive. – Tordek Jun 19 '09 at 17:48

score 5 · Answer 4 · answered Jun 19 '09 at 17:44

5

strpos

<?php
$text = "I go to school";
$word = "to"
$pos = strpos($text, $word);

if ($pos === false) {
    return false;
} else {
    return true;
}
?>

answered Jun 19 '09 at 17:44

jitter

53,475
11
111
124

Eineki · Answer 5 · 2009-06-19T18:06:02.340

3

$text="I go to school";
return (strpos($text, 'to')!== false);

The manual page you need to find the correct usage of strpos

edited Jun 19 '09 at 18:06

answered Jun 19 '09 at 17:45

Eineki

14,773
6
50
59

score 1 · Answer 6 · answered Jun 19 '09 at 17:47

1

Another way (besides the strpos examples already given is to use the 'strstr' function:

if (strstr($haystack, $needle)) {
   return true;
} else {
   return false;
}

answered Jun 19 '09 at 17:47

ylebre

3,100
1
18
14

Arshid KV · Answer 7 · 2020-07-05T06:10:46.340

1

PHP 8 New Function str_contains

if (str_contains('Foo Bar Baz', 'Foo')) {
  echo 'Found';
}

OR

Use strpos function in php .

$text = "I go to school";
$word = "to"
if (strpos($text,$word) !== false ) {
    echo 'true';
}

edited Jul 05 '20 at 06:10

answered Aug 27 '15 at 17:03

Arshid KV

9,631
3
35
36

score 1 · Answer 8 · answered Mar 15 '17 at 12:05

You can use these string functions,

strstr — Find the first occurrence of a string

stristr — Case-insensitive strstr()

strrchr — Find the last occurrence of a character in a string

strpos — Find the position of the first occurrence of a substring in a string

strpbrk — Search a string for any of a set of characters

If that doesn't help then you should use preg regular expression

preg_match — Perform a regular expression match

score -1 · Answer 9 · answered Jun 13 '11 at 08:58

-1

@mrclay

cant' we simply do

"/(?:^|\w+)" . preg_quote($word, '/') . "(?:$|\w+)/i"

so that it either checks starting or whitespace, and ending or whitespace.

answered Jun 13 '11 at 08:58

acpmasquerade

1,880
1
18
15

How can I check if a word is contained in another string using PHP?

9 Answers9

@mrclay

Linked

Related