为什么我不能向从数据库中获取的电子邮件地址发送电子邮件？ [复制]

Question

我的网站允许用户向我的数据库中保存的给定电子邮件地址发送电子邮件。现在我的网站已经上线，我正在测试这样的东西，结果发现我的contact.php 无法正常工作。当我尝试发送电子邮件时，我总是收到消息Sorry, there was an error sending your message.。

我的 Contact.php 有以下代码

<?php
error_reporting(E_ALL);
ini_set('display_errors', 1);
include 'dbcontroller.php';
if (isset($_POST['sendMessage'])) {
    if(empty($_POST['firstname']) || empty($_POST['lastname']) || empty($_POST['email']) || empty($_POST['message'])) {
        echo "<script type='text/javascript'>alert('Please fill all the fields.');window.location.href='contact.php'</script>";
    }
    else{
        $sql = "SELECT * from contact";
        $result = mysqli_query($conn, $sql);
        $row = mysqli_fetch_array($result);
        $to = $row['email'];
        $firstname = $_POST['firstname'];
        $lastname = $_POST['lastname'];
        $mailfrom = $_POST['email'];
        $message = $_POST['message'];
        $headers = "From:" . $firstname . " " . $lastname . "\r\n" . $mailfrom;
    if (mail($to, $message, $headers)) {

     echo "<script type='text/javascript'>alert('Your email has been sent! Thank you for contacting us!');window.location.href='contact.php'</script>";
    }
    else{
        echo "<script type='text/javascript'>alert('Sorry there was an error sending your message.');window.location.href='contact.php'</script>";
        }
}
} 
?>

这是我的联系表格，与 PHP 代码位于同一页面中。

<form method="post" action"">

    <label>First Name </label>
<input type="text" class="form-control" placeholder="Firstname" name="firstname" required="required" />

    <label>Last Name</label>
<input type="text" class="form-control" placeholder="Lastname" name="lastname" required="required"/>

    <label>Email-address</label>
<input type="email" class="form-control" placeholder="Email" name="email" required="required" maxlength="200"/>

    <label>Message </label>
<textarea name="message" class="form-control" required="required" rows="4" cols="50" maxlength="500"></textarea>

    <input type="submit" name="sendMessage" value="Send Email" class="btn btn-primary pull-right"/>
</form>

Answer 1

起初，我看到的是，$fn 和 $ln 没有在任何地方填写，所以它们是空白值。这可能是原因之一。 我看到的另一件事是标题。我认为他们缺少一些最小的东西。 以下是我经常使用的：

[片段]

$headers = "From: $botmail\n"; // Who the email was sent from
$headers .= "MIME-Version: 1.0\n";
$headers .= "Content-Type: text/plain; charset=UTF-8\n";
$headers .= "X-Priority: $priority\n"; // The priority of the mail

$success = mail($receivermail, $subject, $message, $headers);