Slashes automatically added to text boxes php - php

Question

I have been racking my brain to understand why there are slashes ("/") in every one of by textboxes on my page when I run this php script. Everything on the page works fine. I have tried everything but they're just there. Here my whole code below. Thanks for any help!
function validateInput($data, $fieldName){
global $error;
if (empty($data)){
echo "\"$fieldName\" is a required field.<br />\n";
++$error;
$retval = "";
} else if (!preg_match('/[^A-Za-z]/', $data) == 0){
echo "\"$fieldName\" can only contain letters.<br />\n";
++$error;
$retval = "";
} else {
$retval = trim($stripslashes($data));
}
return ($retval);
}
function validateAddress($data, $fieldName){
global $error;
if (empty($data)){
echo "\"$fieldName\" is a required field.<br />\n";
++$error;
$retval = "";
} else if (!preg_match('/[^0-9A-Za-z]/', $data)){
echo "\"$fieldName\" can only contain letters or numbers.<br />\n";
++$error;
$retval = "";
} else {
$retval = trim(stripslashes($data));
}
return ($retval);
}
function validateNumber($data, $fieldName){
global $error;
if (empty($data)){
echo "\"$fieldName\" is a required field.<br />\n";
++$error;
$retval = "";
} else if (!is_numeric($data)){
echo "\"$fieldName\" must contain only numbers.<br />";
++$error;
$retval = "";
} else if (strlen($data) != 10){
echo "\"$fieldName\" must be 10 numbers long.<br />";
++$error;
$retval = "";
} else {
$retval = trim(stripslashes($data));
}
return ($retval);
}
function validateEmail($data, $fieldName){
global $error;
if (empty($data)){
echo "\"$fieldName\" is a required field.<br />\n";
++$error;
$retval = "";
} else {
$retval = trim(stripslashes($input));
$pattern = "/^[\w-]+(\.[\w-]+)*#" .
"[\w-]+(\.[\w-]+)*" .
"(\.[a-z]{2,})$/i";
if (preg_match($pattern, $retval) == 0){
echo "\"$fieldName\" is not a valid email address.<br />\n";
++$error;
}
}
return($retval);
}
function displayForm($name, $email, $address, $phone){
include("header.html");
?>
<div class="center">
<form name="contact_us" action="contact_us.php" method="post">
<p>Your Name: <input type="text" name="name" value=<?php echo $name; ?> /></p>
<p>Your Email: <input type="text" name="email" value=<?php echo $email; ?> /></p>
<p>Your Address: <input type="text" name="address" value=<?php echo $address; ?> /></p>
<p>Your Phone Number: <input type="text" name="phone" value=<?php echo $phone;?> /></p>
<p><input type="submit" name="Submit" value="Send" />
<input type="reset" value="Clear"/>
</form>
</div>
<?php
include("footer.html");
}
$showForm = TRUE;
$error = 0;
$name = "";
$email = "";
$address = "";
$phone = "";
if (isset($_POST['Submit'])){
$name = validateInput($_POST['name'], "Name");
$email = validateEmail($_POST['email'], "Email");
$address = validateAddress($_POST['address'], "Address");
$phone = validateNumber($_POST['phone'], "Phone");
if ($error == 0)
$showForm = FALSE;
else
$showForm = TRUE;
}
if ($showForm == TRUE){
if ($error > 0)
echo "<p>Please re-enter the form information below.<br/>\n";
displayForm($name, $email, $address, $phone);
} else {
echo "Your contact information has been recorded. Thank you!";
}
?>

Answer 1

You have to quote your value attributes in these lines:
<input type="text" name="name" value=<?php echo $name; ?> />
If $name is empty, which is true by default, your code reduces to
<input type="text" name="name" value=/ >
So your input boxes are filled with a / by default. To fix this error (and avoid other possible errors), quote your $name:
<input type="text" name="name" value="<?php echo htmlspecialchars($name); ?>" />
Notice that I also called htmlspecialchars to prevent XSS.

Answer 2

PHP runs addslashes() on all GET, POST, and COOKIE data by default.