php使用smtp发送邮件不需要第三方扩展

1，创建html页面如图（index.html）

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta charset="utf-8">
<title>PHP利用smtp类发送邮件范例</title>
</head>
<body>
<form action="sendmail.php" method="post">
<p>收件人：<input type="text" name="toemail" /></p>
<p>标题：<input type="text" name="title" /></p>
<p>内容：<textarea name="content" cols="50" rows="5"></textarea></p>
<p><input type="submit" value="发送" /></p>
</form>
</body>
</html>
2,创建请求 (sendmail.php）

<?php

class Smtp
{
var $smtp_port;
var $time_out;
var $host_name;
var $log_file;
var $relay_host;
var $debug;
var $auth;
var $user;
var $pass;
var $sock;

function Smtp($relay_host = "", $smtp_port = 25, $auth = false, $user, $pass)
{
$this->debug = FALSE;
$this->smtp_port = $smtp_port;
$this->relay_host = $relay_host;
$this->time_out = 3600;
$this->auth = $auth;
$this->user = $user;
$this->pass = $pass;
$this->host_name = "localhost";
$this->log_file = "";
$this->sock = FALSE;
}

function smtp_sockopen($address)
{
if ($this->relay_host == "") {
return $this->smtp_sockopen_mx($address);
} else {
return $this->smtp_sockopen_relay();
}
}

function smtp_sockopen_relay()
{
$this->log_write("Trying to " . $this->relay_host . ":" . $this->smtp_port . " ");
$this->sock = @fsockopen($this->relay_host, $this->smtp_port, $errno, $errstr, $this->time_out);
if (!($this->sock && $this->smtp_ok())) {
$this->log_write("Error: Cannot connenct to relay host " . $this->relay_host . " ");
$this->log_write("Error: " . $errstr . " (" . $errno . ") ");
return FALSE;
}
$this->log_write("Connected to relay host " . $this->relay_host . " ");
return TRUE;
}

function smtp_message($header, $body)
{
fputs($this->sock, $header . " " . $body);
$this->smtp_debug("> " . str_replace(" ", " " . "> ", $header . " > " . $body . " > "));
return TRUE;
}

function smtp_eom()
{
fputs($this->sock, " . ");
$this->smtp_debug(". [EOM] ");
return $this->smtp_ok();
}

function smtp_ok()
{
$response = str_replace(" ", "", fgets($this->sock, 512));
$this->smtp_debug($response . " ");
if (!ereg("^[23]", $response)) {
fputs($this->sock, "QUIT ");
fgets($this->sock, 512);
$this->log_write("Error: Remote host returned "" . $response . "" ");
return FALSE;
}
return TRUE;
}

function smtp_putcmd($cmd, $arg = "")
{
if ($arg != "") {
if ($cmd == "") $cmd = $arg;
else $cmd = $cmd . " " . $arg;
}
fputs($this->sock, $cmd . " ");
$this->smtp_debug("> " . $cmd . " ");
return $this->smtp_ok();
}

function smtp_error($string)
{
$this->log_write("Error: Error occurred while " . $string . ". ");
return FALSE;
}

function strip_comment($address)
{
$comment = "([^()]*)";
while (ereg($comment, $address)) {
$address = ereg_replace($comment, "", $address);
}
return $address;
}

function get_address($address)
{
$address = ereg_replace("([ ])+", "", $address);
$address = ereg_replace("^.*<(.+)>.*$", "1", $address);
return $address;
}

function smtp_debug($message)
{
if ($this->debug) {
echo $message;
}
}
}

?>
任何获取客户端授权密码；

登入自己的163邮箱
点击设置->常规设置->客户端授权密码;
设置自己的客户端授权密码就行了，
填入相应的文件中，就可以测试了