Contact Form help pls

[duock]

i use this contact form php code, but when i try to send but it didt work, just tell me "No email address added. Please go back.", this is not my code, i just get it from other web, is anything wrong is this code? please help me if u can. thx

<?php

//variables (change these)

$youremail = "[e-mail]";
// your email address

$subject = "Contact";
// the subject of the email

$thankyou = "thankyou.php";
// thank you page

// don't change anything else

if($email == ""){
?>
No email address added. Please go back.<br/>
<?php
}elseif($name == ""){
?>
No name added. Please go back.<br/>
<?php
}elseif($message == ""){
?>
No message added. Please go back.<br/>
<?php
}else{

$msg = ereg_replace("\\'", "'", $message);
$msg = ereg_replace('\\"', "\"", $msg);
$message1 = "from: $name\nemail: $email\nmessage:\n$msg1";

mail($youremail, $subject, $msg, "From: $email\r\nReply-to: $email\r\n");
?>
<meta http-equiv="refresh" content="0; url=<?echo $thankyou;?>"">
<?php
}
?>

<form action="mail.php" method="post">
Name <input type="text" name="name"><br/>
Email addess <input type="text" name="email"><br/>
Message<br/>
<textarea name="message" cols="40" rows="5"></textarea><br/>
<input type="submit" value="send"><br/>
</form>

[ednark]

it seems like this code is assuming that variables from a form are mapped into the local space... that <input name="foo" value="bar"> becomes $foo=$bar

this happend when register_globals is on, as was default in earlier versions of php

nowadays form submitted variables are stored in one of two arrays
$GET if <form method="get"> is used or index.php?foo=bar is used
$POST if <form method="post"> is used

so in that example code

if($email == ""){

should be

if ( empty($_POST['email']) {

etc with all the variables you did not define yourself.

[halojoy]

form will result in 3 $POST variables:
name, mail, message and of course submit
toget the variables, you use:

<?php
// if $_POST['submit'];
$name = $_POST['name'];
$mail = $_POST['mail'];
$message = $_POST['message'];
// here you can test if email is correct [e-mail]
// and if name or message is empty

exit;

// else not $_POST['submit'];

//present HTML FORM
?>
<!-- here is your form -->

<?php

//variables (change these)

$youremail = "[e-mail]";
// your email address

$subject = "Contact";
// the subject of the email

$thankyou = "thankyou.php";
// thank you page

// don't change anything else

if($email == ""){
?>
No email address added. Please go back.<br/>
<?php
}elseif($name == ""){
?>
No name added. Please go back.<br/>
<?php
}elseif($message == ""){
?>
No message added. Please go back.<br/>
<?php
}else{

$msg = ereg_replace("\\\'", "'", $message);
$msg = ereg_replace('\\\"', "\"", $msg);
$message1 = "from: $name\nemail: $email\nmessage:\n$msg1";

mail($youremail, $subject, $msg, "From: $email\r\nReply-to: $email\r\n");
?>
<meta http-equiv="refresh" content="0; url=<?echo $thankyou;?>"">
<?php
}
?>


<form action="mail.php" method="post">
Name <input type="text" name="name"><br/>
Email addess <input type="text" name="email"><br/>
Message<br/>
<textarea name="message" cols="40" rows="5"></textarea><br/>
<input type="submit" value="send"><br/>
</form>

with colors I can see better what is happening here