PHP form required field error message

Question

Ok, I'm pretty clueless when it comes to PHP. I'm new to it and I manage to adjust code to my needs but there is something that I just can't get done. I have this contact form and the PHP looks like this:

<?php
/* Set e-mail recipient */
$myemail  = "";

/* Check all form inputs using check_input function */
$naam = check_input($_POST['naam'], "Vul uw naam in");
$bedrijf  = check_input($_POST['bedrijf']);
$email  = check_input($_POST['email'], "Vul uw emailadres in");
$telefoonnummer  = check_input($_POST['telefoonnummer']);
$onderwerp = check_input($_POST['onderwerp'], "Vul een onderwerp in");
$bericht = check_input($_POST['bericht'], "Stel een vraag of plaats een opmerking");

/* If e-mail is not valid show error message */
if (!preg_match("/([\w\-]+\@[\w\-]+\.[\w\-]+)/", $email))
{
show_error("Vul een geldig e-mailadres in");
}

/* Let's prepare the message for the e-mail */
$message = "Beste,

Een bezoeker heeft een bericht gestuurd:

Naam: $naam
E-mail: $email

Onderwerp: $onderwerp
Bericht:
$bericht

Met vriendelijke groet,
$naam
";

/* Send the message using mail() function */
mail($myemail, $onderwerp, $message);

/* Redirect visitor to the thank you page */
header('Location: thanks.htm');
exit();

/* Functions we used*/ 
function check_input($data, $problem='')
{
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
if ($problem && strlen($data) == 0)
{
    show_error($problem);
}
return $data;
}

function show_error($myError)
{
?>
<html>
<body>

<b>Please correct the following error:</b><br />
<?php echo $myError; ?>

</body>
</html>
<?php
exit();
}
?>

The form has four required fields $naam, $email, $onderwerp and $bericht. After clicking the submit button and any of those aren't filled in, it gives an error. So far so good but it posts the error in a new window, overwriting the contacform. I want the error messages to be displayed on the form itself. I just don't see how to do it and I couldn't find a good answer to this matter online that I could implement in my code.

Any of you could shine a light on this?

You mean without reloading? Then you need some client-side validation with javascript. But please be aware that you should always validate your data on the server too, because javascript can easily be turned of. — kufi
– kufi, Commented Apr 24, 2012 at 8:36

Husman · Accepted Answer · 2012-04-24 08:46:39Z

1

You need to post the HTML form back to itself. Then at the top of the form page, you need an if statement that does a check like this:

if(isset($_POST['submit'])) {
 //do validation
 //$errorMessage = "whatever message you want to show the user"
 if ($errors == 0){
  /* Redirect visitor to the thank you page */
  header('Location: thanks.htm');
  exit();
 }
}

and when displaying the form:

if(isset($errorMessage))
  print $errorMessage;

answered Apr 24, 2012 at 8:46

Husman

6,93910 gold badges32 silver badges48 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

user1067001 · Accepted Answer · 2012-04-24 08:45:13Z

0

You might like to make the following changes:

alert(<?php echo $myError; ?>);

to

<?php echo $myError; ?>

answered Apr 24, 2012 at 8:45

user1067001

Collectives™ on Stack Overflow

PHP form required field error message

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related