PHP contact form detect words in a text field

Question

I have a contact form with a text field for people to enter the name of their company/organization. I want to prevent the form from being submitted if it contains any or variation of any the following words,: uc, uci, irvine, ucirvine. Here is my script:

// company group
    if(trim($_POST['cmpnyGrp']) === '') {
        $cmpnyGrpError = '<span class="error">Please enter your company or group name.</span>';
        $hasError = true;
    } else if (isset($_POST['cmpnyGrp'])) {
        $banned = array('uci', 'uc', 'ucirvine', 'uc-', 'uc ', 'irvine');
        $cmpnyGrpError = '<span class="error">If you are UCI, select UC under User Type and enter account string.</span>';
        $hasError = true;
    } else {
        $cmpnyGrp = trim($_POST['cmpnyGrp']);
    }

I know I am doing something wrong because this isn't working. Im not a programmer, but I am doing my best to try to understand what to do. Any assistance would be greatly appreciated. Thank you very much.

Answer 1

Right now, you initialize $banned and then never use it. You need an if(in_array($_POST['cmpnyGrp'], $banned) {...} . This will check whether the value of cmpnyGrp is in the array of banned words. However, note that such a form of blacklisting can never check for each possible variation of "uc".

Answer 2

You're declaring an array of banned words but doing nothing with it. You need to use it something like as follows:

foreach ($banned as $b) {
    if (strpos($_POST['cmpnyGrp'], $b) !== false) {
        $cmpnyGrpError = '<span class="error">If you are UCI, select UC under User Type and enter account string.</span>';
        $hasError = true;
        break;
    }
}

if (!isset($hasError)) {
    $cmpnyGrp = trim($_POST['cmpnyGrp']);
}

Answer 3

Try this:

if(trim($_POST['cmpnyGrp']) === '') {
    $cmpnyGrpError = '<span class="error">Please enter your company or group name.</span>';
    $hasError = true;
} else {
    $banned = array('uci', 'uc', 'ucirvine', 'uc-', 'uc ', 'irvine');
    $found = false;
    foreach ($banned as $b) {
        if (stripos($_POST['cmpnyGrp'], $b)) {
            $found = true;
            break; // no need to continue looping, we found one match
        }
    }
    if ($found) {
        $cmpnyGrpError = '<span class="error">If you are UCI, select UC under User Type and enter account string.</span>';
        $hasError = true;
    } else {
        $cmpnyGrp = trim($_POST['cmpnyGrp']);
    }
}