Check if an array of words exist in a string - php

Question

We have a function in PHP, in_array, which checks if the given value is present in an array. I guess I wanna do a reverse of it. I have a set of strings:
$words = array("hello", "world");
And, I wanna check, if a given string has these words, by giving parameters whether all or any.
$string = "Hello, World!";
$second = "Hello and Welcome!";
in_string($words, $string, "all");
in_string($words, $string, "any");
What I have right now is, using stripos(). I do not wanna use regex.
Current Code:
<?php
/**
* Checks if the given words is found in a string or not.
*
* #param Array $words The array of words to be given.
* #param String $string The string to be checked on.
* #param String $option all - should have all the words in the array. any - should have any of the words in the array
* #return boolean True, if found, False if not found, depending on the $option
*/
function in_string ($words, $string, $option)
{
if ($option == "all")
foreach ($words as $value)
$isFound = $isFound && (stripos($string, $value) || false);
else
foreach ($words as $value)
$isFound = $isFound || (stripos($string, $value) || false);
return $isFound;
}
?>
My question is, can this be improved? Any thoughts?
Update #1: Current Code Updated:
/**
* Checks if the given words is found in a string or not.
*
* #param Array $words The array of words to be given.
* #param String $string The string to be checked on.
* #param String $option all - should have all the words in the array. any - should have any of the words in the array
* #return boolean True, if found, False if not found, depending on the $option
*/
function in_string ($words, $string, $option)
{
if ($option == "all")
{
$isFound = true;
foreach ($words as $value)
$isFound = $isFound && (stripos($string, $value) !== false);
return $isFound;
}
else
{
$isFound = true;
foreach ($words as $value)
if (stripos($string, $value) !== false) return true;
return $isFound;
}
}
Now the function is working as expected. But I need a better performance in the foreach() part and all. Anything possible for improvements?
Update #2: Improvements Added
<?php
/**
* Checks if the given words is found in a string or not.
*
* #param Array $words The array of words to be given.
* #param String $string The string to be checked on.
* #param String $option all - should have all the words in the array. any - should have any of the words in the array
* #return boolean True, if found, False if not found, depending on the $option
*/
function in_string ($words, $string, $option)
{
if ($option == "all")
{
foreach ($words as $value)
if (stripos($string, $value) === false)
return false;
return true;
}
else
{
foreach ($words as $value)
if (stripos($string, $value) !== false)
return true;
return false;
}
}
?>

Answer 1

<?php
/**
* Checks if the given words is found in a string or not.
*
* #param Array $words The array of words to be given.
* #param String $string The string to be checked on.
* #param String $option all - should have all the words in the array. any - should have any of the words in the array
* #return boolean True, if found, False if not found, depending on the $option
*/
function in_string ($words, $string, $option)
{
if ($option == "all") {
$isFound = true;
foreach ($words as $value) {
$isFound = $isFound && (stripos($string, $value) !== false); // returns boolean false if nothing is found, not 0
if (!$isFound) break; // if a word wasn't found, there is no need to continue
}
} else {
$isFound = false;
foreach ($words as $value) {
$isFound = $isFound || (stripos($string, $value) !== false);
if ($isFound) break; // if a word was found, there is no need to continue
}
}
return $isFound;
}
?>
Just the same code as the person below me, with the break; added. I don't have enough rep to comment apparently

Answer 2

Divide the logic and you'll get simpler code in each function, better performance and each function will solve a concrete task.
<?php
function in_string_all ($string, $words) {
$isFound = true;
foreach ($words as $value) {
$isFound = $isFound && stripos($string, $value) !== false;
if (!$isFound)
break;
}
return $isFound;
}
function in_string_any ($string, $words) {
foreach ($words as $value)
if (stripos($string, $value) !== false)
return true;
return false;
}
?>

Answer 3

Using strpos does not work because it will return true for partial string matches. examples searching "in" in "insersection" results in a false positive.
Here is an alternative extracting words from the target string and making an intersection between arrays.
/**
* Checks if a array of given words is found in a string.
*
* #param array $words The array of words to be given.
* #param string $string The string to be checked on.
* #param boolean $exactMatch true - should have all the words in the array. false - should have any of the words in the array
* #param boolean $insensitive true to compare insensitive. false to compare sensitive
* #return boolean True, if found, False if not found, depending on the $option
*/
private function arrayInString (array $words, $string, $exactMatch = true, $insensitive = true)
{
$stringArr = explode(" ", preg_replace('/[^a-z0-9]+/i', ' ', $string));
if ($insensitive) {
$words = array_map('strtolower', $words);
$stringArr = array_map('strtolower', $stringArr);
}
$intersectionCount = count(array_intersect($words, $stringArr));
if ($exactMatch && $intersectionCount == count($words)) {
return true;
}
if (!$exactMatch && $intersectionCount > 0) {
return true;
}
return false;
}

Answer 4

Use strpos() instead of substr() or strstr() because you only care about the word being present, you don't need to parse anything out. According to the docs, it is faster.
From the Manual:
If you only want to determine if a particular needle occurs within haystack, use the faster and less memory intensive function strpos() instead.

Answer 5

You need to init $isFound, use stripos() for case-insensitive search, and check that stripos() returns false, not 0. (0 means that $string starts with $value)
function in_string ($words, $string, $option)
{
if ($option == "all") {
$isFound = true;
foreach ($words as $value) {
$isFound = $isFound && (stripos($string, $value) !== false);
}
} else {
$isFound = false;
foreach ($words as $value) {
$isFound = $isFound || (stripos($string, $value) !== false);
}
}
return $isFound;
}