PHP Feedback form Checkbox error

Question

Ok here is a shortened version of the php for my contact form, (the checkboxes are not being sent through correctly)

<?php
 //please fill this in at least!
$myemail = "";
$title = "Feedback Form"; 
if(isset($_POST['submit'])) { //form has been submitted
//set variables with filters
$cont_name = filter_var($_POST['cont_name'], FILTER_SANITIZE_STRING);
$email = filter_var($_POST['cont_email'], FILTER_SANITIZE_STRING);
$phone = filter_var($_POST['cont_phone'], FILTER_SANITIZE_STRING);
$first_time = filter_var($_POST['first_time'], FILTER_SANITIZE_STRING);
$hear_about = filter_var($_POST['hear_about'], FILTER_SANITIZE_STRING);

function valid_email($str){
    return ( ! preg_match("/^([a-z0-9\+_\-]+)(\.[a-z0-9\+_\-]+)*@([a-z0-9\-]+\.)+[a-z]{2,6}$/ix", $str)) ? FALSE : TRUE;} 

    $errors = 0; //by default there are no errors

    $trimcont_name = trim($cont_name);
    if(empty($trimcont_name)){
        //the name field is empty
        $errors = 1; //tips off the error messages below
        $errorcont_name = "The name field is empty"; //this error is displayed next to the label
    }
    if(!valid_email($email)) {
        //email is invalid or empty
        $errors = 1;
        $erroremail = "The email address was not valid";
    }
    $trimphone = trim($phone);
    if(empty($trimphone)){
        //the phone field is empty
        $errors = 1;
        $errorphone = "The phone field is empty";
    }
    $trimfirst_time = trim($first_time);
    if(empty($trimfirst_time)){
        //the first_time field is empty
        $errors = 1;
        $errorfirst_time = "This field is empty";
    }
    $trimhear_about = trim($hear_about);
    if(empty($trimhear_about)){
        //the hear_about field is empty
        $errors = 1;
        $errorhear_about = "This field is empty";
    }
    if($spam != "") {
        //spam was filled in
        $errors = 1;
        $errorspam = "The Spam box was filled in";
    }

    if($errors == 0) {
        $sendto = $myemail;
        $message = <<<DATA
DETAILS

Name: $cont_name 
Email: $email
Phone: $phone

Was this the first time you have been to us?
$first_time
How did you hear about us?
$hear_about

DATA;
        $headers = 'From: ' . $name . '<' . $email . '>';
           if(mail($sendto, $title, $message, $headers)) {
                //this is where it sends, using the php mail function
                $success = true;
                //set all the variables to blank to prevent re-submitting.
                $cont_name = "";
                $email = "";
                $phone = "";
                $hear_about = "";
                $first_time = "";
 } else {
                $success = false;
            }

    } else {
        $success = false;
    }
}

?>

And the area not functioning correctly is

<fieldset>
    <legend>How did you hear about us? <span class="phpformerror"><?php echo $errorhear_about; ?></span></legend>
    <div><input type="checkbox" name="hear_about[]" value="Web" /> Web</div>
    <div><input type="checkbox" name="hear_about[]" value="Newspaper" /> Newspaper</div>
    <div><input type="checkbox" name="hear_about[]" value="Radio" /> Radio</div>
    <div><input type="checkbox" name="hear_about[]" value="Driving" /> Driving Past</div>
    <div><input type="checkbox" name="hear_about[]" value="Referal" /> Referal</div>
    <div><input type="checkbox" name="hear_about[]" value="Other" /> Other</div>
</fieldset>

At the moment it will only come through displaying one of the variables if multiple variables are selected.

themerlinproject · Accepted Answer · 2011-12-09 09:39:09Z

2

hear_about is an array and filter_var() does not handle arrays correctly. Instead use filter_var_array():

$hear_about = filter_var_array($_POST['hear_about'], FILTER_SANITIZE_STRING);

Remember that $hear_about is an array, and must be treated like one throughout your code (e.g. just using $hear_about won't work, it needs to be $hear_about[0], $hear_about[1], etc).

So for example in your trim line you would need something like:

foreach($hear_about as $key => $value) {
$trimhear_about[$key] = trim($value);
    if(empty($trimhear_about[$key])){
        //the hear_about field is empty
        $errors = 1;
        $errorhear_about[$key] = "This field is empty";
    }
}

This will preserve the benefits of dealing with an array.

edited Dec 9, 2011 at 9:39

answered Dec 9, 2011 at 9:28

themerlinproject

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3 Comments

lorenzo-s Over a year ago

You are right, this works for sanitizing the strings contained in the array. But not solve the user's problem because in the rest of the script he use $hear_about as if it's a string.

user966834 Over a year ago

hey thankyou for the feedback, this works perfectly until say you were to fill in the form and miss the checkboxes completely. At which point i would get 2 errors: Warning: filter_var_array() expects parameter 1 to be array, null given in… , & Warning: Invalid argument supplied for foreach() relating to the code thats been included as you've advised.

themerlinproject Over a year ago

you could use is_array to determine if it is an array and react accordingly

Community · Accepted Answer · 2023-11-17 19:59:20Z

0

$_POST['hear_about'] is an array of values. You are handling it as a simple string!

I think you can solve simply replacing the line:

$hear_about = filter_var($_POST['hear_about'], FILTER_SANITIZE_STRING);

With:

$hear_about = filter_var(implode(', ', $_POST['hear_about']), FILTER_SANITIZE_STRING);

The implode function (doc) "transform" an array to a string by concatenating the array values with the given glue. So you can just concatenate selected "How did you hear about us?" options with a comma and then use the resulting string as the other data.

edited Nov 17, 2023 at 19:59

CommunityBot

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answered Dec 9, 2011 at 9:29

lorenzo-s

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1 Comment

themerlinproject Over a year ago

easier to use 'filter_var_array' which is designed for this exact scenario

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