<?php
include "db_conn.php";//connection file
require "PHPMailerAutoload.php";// it will be in PHPMailer
require "class.smtp.php";// it will be in PHPMailer
require "class.phpmailer.php";// it will be in PHPMailer


$response = array();
$params = json_decode(file_get_contents("php://input"));

if(!empty($params->email_id)){

    $email_id = $params->email_id;
    $flag=false;
    echo "something";
    if(!filter_var($email_id, FILTER_VALIDATE_EMAIL))
    {
        $response['ERROR']='EMAIL address format error'; 
        echo json_encode($response,JSON_UNESCAPED_SLASHES);
        return;
    }
    $sql="SELECT * from sales where email_id ='$email_id' ";

    $result = mysqli_query($conn,$sql);
    $count = mysqli_num_rows($result);

    $to = "demo@gmail.com";
    $subject = "DEMO Subject";
    $messageBody ="demo message .";

    if($count ==0){
        $response["valid"] = false;
        $response["message"] = "User is not registered yet";
        echo json_encode($response);
        return;
    }

    else {

        $mail = new PHPMailer();
        $mail->IsSMTP();
        $mail->SMTPAuth = true; // authentication enabled
        $mail->IsHTML(true); 
        $mail->SMTPSecure = 'ssl';//turn on to send html email
        // $mail->Host = "ssl://smtp.zoho.com";
        $mail->Host = "p3plcpnl0749.prod.phx3.secureserver.net";//you can use gmail 
        $mail->Port = 465;
        $mail->Username = "demousername@example.com";
        $mail->Password = "demopassword";
        $mail->SetFrom("demousername@example.com", "Any demo alert");
        $mail->Subject = $subject;

        $mail->Body = $messageBody;
        $mail->AddAddress($to);
        echo "yes";

        if(!$mail->send()) {
           echo "Mailer Error: " . $mail->ErrorInfo;
       } 
       else {
           echo "Message has been sent successfully";
      }
    }

}
else{
    $response["valid"] = false;
    $response["message"] = "Required field(s) missing";
    echo json_encode($response);
}


?>

上面的代码为我工作。

原生PHP函数mail()不适合我。它发出消息:

此邮件服务器在试图发送时需要身份验证 到非本地电子邮件地址

所以，我通常使用PHPMailer包

我已经从GitHub下载了5.2.23版本。

我只选择了2个文件，并将它们放在我的源代码PHP根目录中

class.phpmailer.php class.smtp.php

在PHP中，需要添加该文件

require_once('class.smtp.php');
require_once('class.phpmailer.php');

在此之后，它只是代码:

require_once('class.smtp.php');
require_once('class.phpmailer.php');
... 
//----------------------------------------------
// Send an e-mail. Returns true if successful 
//
//   $to - destination
//   $nameto - destination name
//   $subject - e-mail subject
//   $message - HTML e-mail body
//   altmess - text alternative for HTML.
//----------------------------------------------
function sendmail($to,$nameto,$subject,$message,$altmess)  {

  $from  = "yourcontact@yourdomain.com";
  $namefrom = "yourname";
  $mail = new PHPMailer();  
  $mail->CharSet = 'UTF-8';
  $mail->isSMTP();   // by SMTP
  $mail->SMTPAuth   = true;   // user and password
  $mail->Host       = "localhost";
  $mail->Port       = 25;
  $mail->Username   = $from;  
  $mail->Password   = "yourpassword";
  $mail->SMTPSecure = "";    // options: 'ssl', 'tls' , ''  
  $mail->setFrom($from,$namefrom);   // From (origin)
  $mail->addCC($from,$namefrom);      // There is also addBCC
  $mail->Subject  = $subject;
  $mail->AltBody  = $altmess;
  $mail->Body = $message;
  $mail->isHTML();   // Set HTML type
//$mail->addAttachment("attachment");  
  $mail->addAddress($to, $nameto);
  return $mail->send();
}

这招很管用

你可以做一个测试，如果你需要它通过修补如下代码

# SSH into droplet
# go to project
$ php artisan tinker
$ Mail::send('errors.401', [], function ($message) { $message->to('emmanuelbarturen@gmail.com')->subject('this works!'); });
# check your mailbox

还可以查看PEAR邮件包PEAR mail Page

它似乎比内置的标准mail()函数健壮一些(如果标准函数不够的话)。

下面是该页面的一段摘录，展示如何使用它。PEAR邮件发送()用法

<?php
    include('Mail.php');

    $recipients = 'joe@example.com';

    $headers['From']    = 'richard@example.com';
    $headers['To']      = 'joe@example.com';
    $headers['Subject'] = 'Test message';

    $body = 'Test message';

    $smtpinfo["host"] = "smtp.server.com";
    $smtpinfo["port"] = "25";
    $smtpinfo["auth"] = true;
    $smtpinfo["username"] = "smtp_user";
    $smtpinfo["password"] = "smtp_password";


    // Create the mail object using the Mail::factory method
    $mail_object =& Mail::factory("smtp", $smtpinfo); 

    $mail_object->send($recipients, $headers, $body);
?> 

对于未来的读者:如果其他答案都不管用(就像我的情况一样)，试试这个:

1)。下载PHPMailer，打开zip文件并解压到您的项目目录。

3)。将提取的目录重命名为phpailer，并在php脚本中编写以下代码(脚本必须在phpailer文件夹之外)

<?php
// PHPMailer classes into the global namespace
use PHPMailer\PHPMailer\PHPMailer; 
use PHPMailer\PHPMailer\Exception;
// Base files 
require 'PHPMailer/src/Exception.php';
require 'PHPMailer/src/PHPMailer.php';
require 'PHPMailer/src/SMTP.php';
// create object of PHPMailer class with boolean parameter which sets/unsets exception.
$mail = new PHPMailer(true);                              
try {
    $mail->isSMTP(); // using SMTP protocol                                     
    $mail->Host = 'smtp.gmail.com'; // SMTP host as gmail 
    $mail->SMTPAuth = true;  // enable smtp authentication                             
    $mail->Username = 'sender@gmail.com';  // sender gmail host              
    $mail->Password = 'password'; // sender gmail host password                          
    $mail->SMTPSecure = 'tls';  // for encrypted connection                           
    $mail->Port = 587;   // port for SMTP     

    $mail->setFrom('sender@gmail.com', "Sender"); // sender's email and name
    $mail->addAddress('receiver@gmail.com', "Receiver");  // receiver's email and name

    $mail->Subject = 'Test subject';
    $mail->Body    = 'Test body';

    $mail->send();
    echo 'Message has been sent';
} catch (Exception $e) { // handle error.
    echo 'Message could not be sent. Mailer Error: ', $mail->ErrorInfo;
}
?>

这是非常基本的方法发送纯文本电子邮件使用邮件功能。

<?php
$to = 'SomeOtherEmailAddress@Domain.com';
$subject = 'This is subject';
$message = 'This is body of email';
$from = "From: FirstName LastName <SomeEmailAddress@Domain.com>";
mail($to,$subject,$message,$from);