ping“smtp.gmail.com”可以通，为什么PHPMAILer却报错

<?php
 
include("phpmailer/class.phpmailer.php"); 
$mail             = new PHPMailer(); 
$body             = "TEST_TEST"; 
 
$mail->IsSMTP(); 
$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   = "xxx@gmail.com";  // GMAIL username 
$mail->Password   = "xxx";            // GMAIL password 
 
 
$mail->From       = "xxx@gmail.com"; 
$mail->FromName   = "xxx"; 
 
$mail->Subject    = "subject 111"; 
 
//$mail->Body       = "Hi,<br>This is the HTML BODY<br>";                      //HTML Body 
$mail->AltBody    = "To view the message, please use an HTML compatible email viewer!"; // optional, comment out and test 
$mail->WordWrap   = 50; // set word wrap 
 
$mail->MsgHTML($body); 
 
$mail->AddAddress("xxx@gmail.com", "xxx"); 
 
$mail->IsHTML(true); // send as HTML 
 
if(!$mail->Send()) { 
    echo "Mailer Error: " . $mail->ErrorInfo; 
} else { 
    echo "Message sent!"; 
} 
     
?>