$mailsto = explode(",",$smtpemailto);//截取字符串，以“，”作为分隔符
for ($i=0;$i<count($mailsto);$i++)
{
 $mail->AddAddress($mailsto[$i]); //添加发送的地址
}

2.从数据库中读取数据，显示在select列表中
<?
 
$host = "localhost:3306";
$user = "root";
$password = "";
$database = "ebooklib";
$table = "email";

  $dbh=mysql_connect("$host","$user","$password");
  mysql_select_db($database);
  $query = "select * from $table";
  $res = mysql_query($query, $dbh);
  $data=mysql_fetch_array($res);
  $record=mysql_num_rows($res);

  $record=0;

  echo "<select name=type size=1>\n";
       do{
             if ($record==1){
                echo "<option value=".$data['email']." selected>".$data['email']."</option>\n";
                          }
             else{
                echo "<option value=".$data['email'].">".$data['email']."</option>\n";
             }
       }while($data=mysql_fetch_array($res));
       echo "</select>\n";
 
   
?>

3.php的配置：

一 下载安装程序
下载所需要的php5和Apache2；
二 安装程序
　　1、Apache的程序安装相对来说要较为的简单一些,直接双击运行安装。
　　2、下载下来的PHP包解压到C盘下的根目录下,并将解压出来的文件夹改名为php。
三 配置
1、必须将php5ts.dll文件放到 Windows 路径中。最好的位置是 Windows 的 system 目录：

2.下一步是设定有效的 PHP 配置文件，php.ini。压缩包中包括两个 ini 文件，php.ini-dist 和 php.ini-recommended

。建议使用 php.ini-recommended，因为此文件对默认设置作了性能和安全上的优化。
将php.ini-recommended改名为 php.ini。放到c:\Windows 目录下；
3. Apache中PHP的设置
    插入如下两行到 httpd.conf 中，以使我们的 PHP 作为 Apache 的 PHP-Module 安装：
　　PHP 以模块方式安装到 Apache 2.0:
; For PHP 4 do something like this:
LoadModule php4_module "c:/php/php4apache2.dll"
AddType application/x-httpd-php .php

; For PHP 5 do something like this:
LoadModule php5_module "c:/php/php5apache2.dll"
AddType application/x-httpd-php .php
4.php.ini文件的修改：
doc_root = d：\apache2\htdocs
extension_dir = c:\php\ext
session.save_path = c:/temp
在session.save_path中使用正斜杠和反斜杠都是允许的。
display_errors = On
使用mysql，要将extension=php_mysql.dll前的逗号去掉！
     session.save_path = C:\temp

4.访问数据库基本程序：
<?php

$host = "localhost:3306";
$user = "root";
$password = "";
$database = "ebooklib";
$table = "users";

  $dbh=mysql_connect("$host","$user","$password");
  mysql_select_db($database);
  $query = "insert into users(USER_USERNAME, USER_PASSWORD) values ('wangxq','01')";
  $res = mysql_query($query, $dbh);
  $query = "select max(USER_ID) from $table";
  $res = mysql_query($query, $dbh);
  $err = mysql_error();
  if($err){
   echo "发生错误，请通知<a href=mailto:webmaster@my.site>站长</a>";
  }
  $row = mysql_fetch_row($res);
  echo "你的用户名是：".$row[0];
?>

$mail = new PHPMailer();

$smtpserver = "smtp.126.com:25";

$smtpusermail = "wxq3327@126.com";
$smtpusername = "wangxq";
$smtpemailto = $_POST["to"];
$smtpuser = "wxq3327";
$smtppass = "wxq3327";

$uploaddir = 'c:/temp/';
$uploadfile = $uploaddir . basename($_FILES['attachfile']['name']);

$mailsubject = $_POST["name"]." send to you a mail 【" . $_POST["title"]."】";
$mailbody = $_POST["mail"];

$mail->IsSMTP(); // send via SMTP
$mail->Host = $smtpserver; // SMTP servers
$mail->SMTPAuth = true; // turn on SMTP authentication
$mail->Username = $smtpuser; // SMTP username
$mail->Password = $smtppass; // SMTP password
$mail->CharSet = "UTF-8";

$mail->From = $smtpusermail;
$mail->FromName = $smtpusername;

$mailsto = explode(",",$smtpemailto);
for ($i=0;$i<count($mailsto);$i++)
{
 $mail->AddAddress($mailsto[$i]);
}

if (move_uploaded_file($_FILES['attachfile']['tmp_name'], $uploadfile)) {
    $mail->AddAttachment($uploadfile);
} else {
    echo "Possible file upload attack!\n";
}
$mail->WordWrap = 100; // set word wrap
$mail->IsHTML(true); // send as HTML

$mail->Subject = $mailsubject;
$mail->Body = $mailbody;
$mail->AltBody = $mailbody;

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

echo "Message has been sent";
?>