I have a string in php
$string = "a very long text ...."
I would like to check if this string contains any of the following words
$forbidden_words = array("word1", "word2", "word3");
I know I can use
if (str_contains('abc', '')) { .... }
but this works for only one word. How can I select the string if does not contain any of the words in the array ?
You could form a regex alternation of the blacklisted keywords and then use preg_match():
$string = "a very long text ....";
$forbidden_words = array("word1", "word2", "word3");
$regex = "/\b(?:" . implode("|", $forbidden_words) . ")\b/";
if (!preg_match($regex, $string)) {
echo "MATCH";
}
You can use a loop to iterate over the array of forbidden words and check if any of them exist:
$string = "a very long text ....";
$forbidden_words = array("word1", "word2", "word3");
foreach ($forbidden_words as $word) {
if (str_contains($string, $word)) {
echo "The string contains the word: $word";
}
}
Alternative to check if any of them appear in the string (using strpos) :
$string = "a very long text ....";
$forbidden_words = array("word1", "word2", "word3");
$contains_forbidden_word = false;
foreach ($forbidden_words as $word) {
if (strpos($string, $word) !== false) {
$contains_forbidden_word = true;
break;
}
}
if (!$contains_forbidden_word) {
// The string does not contain any of the forbidden words
}
You can use a regex to check for all the words in one run.
$forbidden_words = array("word1", "word2", "word3");
$string = "a very long text ....";
if(preg_match('/\b(' . implode('|', array_map('preg_quote', $forbidden_words)) . ')\b/')) {
echo 'have forbidden word(s)';
}
This uses word boundaries to ensure partial word matches don't match. In demo below word1 won't match word, vice versa would occur with string functions (e.g. strpos). An i modifier can be added after closing delimiter if this should be case insensitive.
