PHP form still sending after error - php

Question

I am a PHP newb so please bear with me for this rather simplistic question.
I have a PHP form setup like so >>
<?php
if($_POST){
$name = $_POST['name'];
$email = $_POST['email'];
$message = $_POST['message'];
$comments = $_POST['comments'];
if($comments)
$error = "There was an error, please give us a call at ### ###-####.";
else{
if($name=="Name" || $email=="Email" || $message=="Message"){
$error = "All fields are required, please fill them out and try again.";
}else
$header = "From: $name <$email>";
$message = "Name: $name\n\nEmail: $email\n\nMessage: $message";
if(mail("email#domain.com", 'Form Submission', $message, $header))
$success = "Thanks for sending us your message, we'll get back to you shortly.";
else
$error = "There was an error, please give us a call at ### ###-####.";
}
if($error)
echo '<div class="msg error">'.$error.'</div>';
elseif($success)
echo '<div class="msg success">'.$success.'</div>';
}
?>
The basic idea is that the form has descriptive text pre-filled in each field but when you click on them they are cleared via Javascript. I want to prevent people from pressing send on the form without filling it out, hence the "if($name=="Name" || $email=="Email" || $message=="Message"){" bit. However while that message is working the form is still submitting. Why is this. Also please note that the "comments" field is in fact a honeypot. Thanks!

Answer 1

Because php is server-side. You need to look into javascript validation for what you want. To validate with php you HAVE to submit the form.
One tutorial but I recommend Jquery validation

Answer 2

"I want to prevent people from pressing send on the form without filling it out, hence the "if($name=="Name" || $email=="Email" || $message=="Message"){"
All you need to do is disable the submit button client side until the proper validation is met, then also validate server side. As #Iznogood said, that's why your gettin your error

Answer 3

Like lznogood said, PHP validates the form on the server, so you need to send the information to the server before PHP can process it.
If you want the form to be checked on the user side before sending it to the server you should use JavaScript to do that (jQuery is a great tool to use), and after checking it on the user side you can decide whether to send the form to the server or not.

Answer 4

Though this isn't an answer to your question, you might be interest in the new html5 feature placeholder. Read about it here. You can check to see which browsers it works in here (stupid internet explorer!). 5 years ago, I would put those "hints" as the value, which was a pain to validate. placeholder makes it sooooooo much easier. Your tag would look like:
<input type="text" name="email" placeholder="Enter Your Email Here" value="">
Note that value is empty. You can omit the value attribute, I left it in to show it's not needed here.
As far as an answer to your original question, everybody else is correct, javascript is the way to go.