Check if an array element is in a string - php

Question

This question has been asked before about strings, however *none of the questions I've reviewed (not mods do not remove or tell us this is a duplicate please) actually answer my question.
I have a landing page with a simple signup via email box. Recently people have been abusing it by entering foreign characters such as *, #, $, % and also using profanity on purpose (you can always tell). I have an array of banned characters and words I'm using as follows
$banned = array("f**k", "f******", "blah", "*", "#", "$", "%");
I can tell for sure someone has been purposely trying again and again to get through it because I've missed out some characters and suddenly a bunch of addresses have been entered making no sense at all. I need to know how to use a For loop to go through and find if the following contains any of the banned words in the array
$email = $_POST['email'];
I have tried using
$arrlen = count($banned);
for($i=0; $i < $arrlen; $i++) {
if(stripos($email, $banned[$i] !== false) {
echo 'Banned word or character!';
}
else {
echo 'Email signed up!';
}
}
This did not work at all! I tried an old function is_str_contain but the error of function does not exist came back.
I tried the normal strpos as well, still no joy.

Answer 1

I've been tinkering at the idea since I didn't have a ready-made piece of code to help out.
The following works:
$banned = array("badword1", "badword2", "blah", "*", "#", "$", "%");
$_POST['email'] = "emailbadword1#example.com";
$email = $_POST['email'];
foreach ($banned as $ban) {
if (stripos($email, $ban) !== FALSE) {
echo "Match found.";
return true;
}
}
echo "No match found.";
return false;
Plus, as I mentioned in comments; you should be using a confirmation method sent via email if you're not already doing so. If that person does not confirm their email address, then "stop the presses".

Answer 2

Using regular expressions ?
if( !preg_match( '/(\b' . implode( '\b|\b', $banned ) . '\b)/i',
$_POST['email'] )) {
echo "Match found";
}

Answer 3

try like this
$banned = array("****", "*******", "blah", "*", "#", "$", "%");
$email = $_POST['email'];
foreach ($email as $em) {
//if (strstr($em, $banned)) { // mine version
if (strpos($em, $banned) !== FALSE) { // Yoshi version
echo "Match found";
return true;
}
}
echo "Not found!";
return false;

Answer 4

You can use stripos as
foreach ($banned as $v) {
if (stripos($email,$v) > -1){
echo 'Banned word or character!';
}else{
echo 'Email signed up!';
}
}

Answer 5

You will need to iterate through each banned word and look if your email contains any of the banned word/character.
$banned = array("****", "*******", "blah", "*", "#", "$", "%");
$email = $_POST['email'];
$banned = false;
for($i=0; $i < count($banned); $i++) {
if(strrpos($email, $banned[$i]) != FALSE ) {
$banned = true;
break;
}
}
echo $banned ? 'Banned word or character!' : 'Email signed up!'