我已经开始制作一个消息框，用户可以向我发送消息。当我运行代码时，方框工作正常，但我从未收到邮件，我也没有收到任何错误。谁能看出我做错了什么？
<?php
//set validation error flag as false
$error = false;
//check if form is submitted
if (isset($_POST['submit']))
{
$name = trim($_POST['txt_name']);
$fromemail = trim($_POST['txt_email']);
$subject = trim($_POST['txt_subject']);
$message = trim($_POST['txt_msg']);
//name can contain only alpha characters and space
if (!preg_match("/^[a-zA-Z ]+$/",$name))
{
$error = true;
$name_error = "Please Enter Valid Name";
}
if(!filter_var($fromemail,FILTER_VALIDATE_EMAIL))
{
$error = true;
$fromemail_error = "Please Enter Valid Email ID";
}
if(empty($subject))
{
$error = true;
$subject_error = "Please Enter Your Subject";
}
if(empty($message))
{
$error = true;
$message_error = "Please Enter Your Message";
}
if (!$error)
{
//send mail
$toemail = "test@stackoverflow.com";
$subject = "Enquiry from Visitor " . $name;
$body = "Here goes your Message Details: \n\n Name: $name \n From: $fromemail \n Message: \n $message";
$headers = "From: $fromemail\n";
$headers .= "Reply-To: $fromemail";
if (mail ($toemail, $subject, $body, $headers))
$alertmsg = '<div class="alert alert-success text-center">Message sent successfully. We will get back to you shortly!</div>';
else
$alertmsg = '<div class="alert alert-danger text-center">There is error in sending mail. Please try again later.</div>';
}
}
?>
<!DOCTYPE html>
<html>
<head>
<title>Bootstrap 3 Contact Form Example</title>
<meta content="width=device-width, initial-scale=1.0" name="viewport" >
<link rel="stylesheet" href="css/bootstrap.min.css" type="text/css" />
</head>
<body>
<div class="container">
<div class="row">
<div class="col-md-6 col-md-offset-3 well">
<form role="form" class="form-horizontal" action="<?php echo $_SERVER['PHP_SELF']; ?>" method="post" name="contactform">
<fieldset>
<legend>Bootstrap Contact Form</legend>
<div class="form-group">
<div class="col-md-12">
<label for="txt_name" class="control-label">Name</label>
</div>
<div class="col-md-12">
<input class="form-control" name="txt_name" placeholder="Your Full Name" type="text" value="<?php if($error) echo $name; ?>" />
<span class="text-danger"><?php if (isset($name_error)) echo $name_error; ?></span>
</div>
</div>
<div class="form-group">
<div class="col-md-12">
<label for="txt_email" class="control-label">Email ID</label>
</div>
<div class="col-md-12">
<input class="form-control" name="txt_email" placeholder="Your Email ID" type="text" value="<?php if($error) echo $fromemail; ?>" />
<span class="text-danger"><?php if (isset($fromemail_error)) echo $fromemail_error; ?></span>
</div>
</div>
<div class="form-group">
<div class="col-md-12">
<label for="txt_subject" class="control-label">Subject</label>
</div>
<div class="col-md-12">
<input class="form-control" name="txt_subject" placeholder="Your Subject" type="text" value="<?php if($error) echo $subject; ?>" />
<span class="text-danger"><?php if (isset($subject_error)) echo $subject_error; ?></span>
</div>
</div>
<div class="form-group">
<div class="col-md-12">
<label for="txt_msg" class="control-label">Message</label>
</div>
<div class="col-md-12">
<textarea class="form-control" name="txt_msg" rows="4" placeholder="Your Message"><?php if($error) echo $message; ?></textarea>
<span class="text-danger"><?php if (isset($message_error)) echo $message_error; ?></span>
</div>
</div>
<div class="form-group">
<div class="col-md-12">
<input name="submit" type="submit" class="btn btn-primary" value="Send" />
</div>
</div>
</fieldset>
</form>
<?php if (isset($alertmsg)) { echo $alertmsg; } ?>
</div>
</div>
</div>
</body>
</html>