使用Swift mailer，很容易通过Gmail凭据发送邮件:

<?php
require_once 'swift/lib/swift_required.php';

$transport = Swift_SmtpTransport::newInstance('smtp.gmail.com', 465, "ssl")
  ->setUsername('GMAIL_USERNAME')
  ->setPassword('GMAIL_PASSWORD');

$mailer = Swift_Mailer::newInstance($transport);

$message = Swift_Message::newInstance('Test Subject')
  ->setFrom(array('abc@example.com' => 'ABC'))
  ->setTo(array('xyz@test.com'))
  ->setBody('This is a test mail.');

$result = $mailer->send($message);
?>

I have a solution for GSuite accounts that doesnt have the "@gmail.com" sufix. Also I think it will work for GSuite accounts with the @gmail.com but havent tried it. First you should have the privileges to change the option "allos¿w less secure app" for your GSuite account. If you have the privileges (you can check in account settings->security) then you have to deactivate "two step factor authentication" go to the end of the page and set to "yes" for allow less secure applications. That's all. If you dont have privileges to change those options the solution for this thread will not work. Check https://support.google.com/a/answer/6260879?hl=en to make changes to "allow less..." option.

Gmail需要端口465，它也是来自phpmailer的代码

我尝试了@shasi kanth提供的建议，但没有奏效。我读了文档，做了一些改动。所以我设法通过Gmail使用这段代码发送邮件，其中vendor/autoload.php是由作曲家与作曲家要求“swiftmailer/swiftmailer:^6.0”:

<?php
     require_once 'vendor/autoload.php';
     $transport = (new Swift_SmtpTransport('smtp.gmail.com', 465, 'ssl'))->setUsername ('SendingMail')->setPassword ('Password');

     $mailer = new Swift_Mailer($transport);

     $message = (new Swift_Message('test'))
      ->setFrom(['Sending mail'])
      ->setTo(['Recipient mail'])
      ->setBody('Message')
  ;

     $result = $mailer->send($message);
    ?>

要在Ubuntu中安装PEAR的Mail.php，运行以下命令:

    sudo apt-get install php-pear
    sudo pear install mail
    sudo pear install Net_SMTP
    sudo pear install Auth_SASL
    sudo pear install mail_mime

<?php
date_default_timezone_set('America/Toronto');

require_once('class.phpmailer.php');
//include("class.smtp.php"); // optional, gets called from within class.phpmailer.php if not already loaded

$mail             = new PHPMailer();

$body             = "gdssdh";
//$body             = eregi_replace("[\]",'',$body);

$mail->IsSMTP(); // telling the class to use SMTP
//$mail->Host       = "ssl://smtp.gmail.com"; // SMTP server
$mail->SMTPDebug  = 1;                     // enables SMTP debug information (for testing)
                                           // 1 = errors and messages
                                           // 2 = messages only
$mail->SMTPAuth   = true;                  // enable SMTP authentication
$mail->SMTPSecure = "ssl";                 // sets the prefix to the servier
$mail->Host       = "smtp.gmail.com";      // sets GMAIL as the SMTP server
$mail->Port       = 465;                   // set the SMTP port for the GMAIL server
$mail->Username   = "user@gmail.com";  // GMAIL username
$mail->Password   = "password";            // GMAIL password

$mail->SetFrom('contact@prsps.in', 'PRSPS');

//$mail->AddReplyTo("user2@gmail.com', 'First Last");

$mail->Subject    = "PRSPS password";

//$mail->AltBody    = "To view the message, please use an HTML compatible email viewer!"; // optional, comment out and test

$mail->MsgHTML($body);

$address = "user2@yahoo.co.in";
$mail->AddAddress($address, "user2");

//$mail->AddAttachment("images/phpmailer.gif");      // attachment
//$mail->AddAttachment("images/phpmailer_mini.gif"); // attachment

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

?>