如果您正在使用SMTP配置来发送电子邮件，请尝试使用PHPMailer。您可以从https://github.com/PHPMailer/PHPMailer下载该库。

我用这种方式创建了我的电子邮件:

function send_mail($email, $recipient_name, $message='')
{
    require("phpmailer/class.phpmailer.php");

    $mail = new PHPMailer();

    $mail->CharSet = "utf-8";
    $mail->IsSMTP();                                      // Set mailer to use SMTP
    $mail->Host = "mail.example.com";  // Specify main and backup server
    $mail->SMTPAuth = true;     // Turn on SMTP authentication
    $mail->Username = "myusername";  // SMTP username
    $mail->Password = "p@ssw0rd"; // SMTP password

    $mail->From = "me@walalang.com";
    $mail->FromName = "System-Ad";
    $mail->AddAddress($email, $recipient_name);

    $mail->WordWrap = 50;                                 // Set word wrap to 50 characters
    $mail->IsHTML(true);                                  // Set email format to HTML (true) or plain text (false)

    $mail->Subject = "This is a Sampleenter code here Email";
    $mail->Body    = $message;
    $mail->AltBody = "This is the body in plain text for non-HTML mail clients";
    $mail->AddEmbeddedImage('images/logo.png', 'logo', 'logo.png');
    $mail->addAttachment('files/file.xlsx');

    if(!$mail->Send())
    {
       echo "Message could not be sent. <p>";
       echo "Mailer Error: " . $mail->ErrorInfo;
       exit;
    }

    echo "Message has been sent";
}

Debian 10.0.0 ('Buster')的Sendmail安装实际上很简单!

php . ini

[mail function]
sendmail_path=/usr/sbin/sendmail -t -i
; (Other directives are mostly windows)

标准sendmail包安装(允许'send'):

su -                                        # Install as user 'root'
dpkg --list                                 # Is install necessary?
apt-get install sendmail sendmail-cf m4     # Note multiple package selection
sendmailconfig                              # Respond all 'Y' for new install

其他有用的命令:

which sendmail                              # /usr/sbin/sendmail
which sendmailconfig                        # /usr/sbin/sendmailconfig
man sendmail                                # Documentation
systemctl restart sendmail                  # As and when required

验证(发送能力)

echo "Subject: sendmail test" | sendmail -v <yourEmail>@gmail.com

以上花费了大约5分钟。然后我浪费了5个小时…别忘了检查你的垃圾邮件文件夹!

我在000webhost上做了以下工作:

$headers  = "MIME-Version: 1.0" . "\r\n";
$headers .= "Content-type: text/html; charset=iso-8859-1" . "\r\n";
$headers .= "From: ". $from. "\r\n";
$headers .= "Reply-To: ". $from. "\r\n";
$headers .= "X-Mailer: PHP/" . phpversion();
$headers .= "X-Priority: 1" . "\r\n";

发送邮件时直接输入邮箱地址:

mail('email@gmail.com', $subject, $message, $headers)

使用“and not”。

这个代码工作，但电子邮件收到了半小时的延迟。

如果你在本地服务器上运行这段代码(也就是你的计算机用于开发目的)，它不会将电子邮件发送给收件人。它将在名为mailoutput的文件夹中创建一个.txt文件。

在这种情况下，如果您正在使用免费的软管服务，如000webhost或hostinger，这些服务提供商将禁用mail()函数，以防止意外使用电子邮件欺骗，垃圾邮件等。我希望你联系他们，看看他们是否支持这个功能。

如果您确定服务提供者支持mail()函数，您可以查看PHP手册以进一步参考，

PHP邮件()

要检查您的托管服务是否支持mail()函数，请尝试运行这段代码(记得更改收件人的电子邮件地址):

<?php
    $to      = 'nobody@example.com';
    $subject = 'the subject';
    $message = 'hello';
    $headers = 'From: webmaster@example.com' . "\r\n" .
        'Reply-To: webmaster@example.com' . "\r\n" .
        'X-Mailer: PHP/' . phpversion();

    mail($to, $subject, $message, $headers);
?>

如果您正在使用SMTP配置来发送电子邮件，请尝试使用PHPMailer。您可以从https://github.com/PHPMailer/PHPMailer下载该库。

我用这种方式创建了我的电子邮件:

function send_mail($email, $recipient_name, $message='')
{
    require("phpmailer/class.phpmailer.php");

    $mail = new PHPMailer();

    $mail->CharSet = "utf-8";
    $mail->IsSMTP();                                      // Set mailer to use SMTP
    $mail->Host = "mail.example.com";  // Specify main and backup server
    $mail->SMTPAuth = true;     // Turn on SMTP authentication
    $mail->Username = "myusername";  // SMTP username
    $mail->Password = "p@ssw0rd"; // SMTP password

    $mail->From = "me@walalang.com";
    $mail->FromName = "System-Ad";
    $mail->AddAddress($email, $recipient_name);

    $mail->WordWrap = 50;                                 // Set word wrap to 50 characters
    $mail->IsHTML(true);                                  // Set email format to HTML (true) or plain text (false)

    $mail->Subject = "This is a Sampleenter code here Email";
    $mail->Body    = $message;
    $mail->AltBody = "This is the body in plain text for non-HTML mail clients";
    $mail->AddEmbeddedImage('images/logo.png', 'logo', 'logo.png');
    $mail->addAttachment('files/file.xlsx');

    if(!$mail->Send())
    {
       echo "Message could not be sent. <p>";
       echo "Mailer Error: " . $mail->ErrorInfo;
       exit;
    }

    echo "Message has been sent";
}

只需在发送邮件之前添加一些标题:

<?php 
$name = $_POST['name'];
$email = $_POST['email'];
$message = $_POST['message'];
$from = 'From: yoursite.com'; 
$to = 'contact@yoursite.com'; 
$subject = 'Customer Inquiry';
$body = "From: $name\n E-Mail: $email\n Message:\n $message";

$headers .= "MIME-Version: 1.0\r\n";
$headers .= "Content-type: text/html\r\n";
$headers .= 'From: from@example.com' . "\r\n" .
'Reply-To: reply@example.com' . "\r\n" .
'X-Mailer: PHP/' . phpversion();

mail($to, $subject, $message, $headers);

还有一件事。mail()函数在本地主机中不起作用。将代码上传到服务器并尝试。