workorder/application/libraries/Mailer.php

<?php
if (!defined('BASEPATH')) exit('No direct script access allowed');

require_once "PHPMail/PHPMailerAutoload.php";
class Mailer
{
    var $mail;

    public function __construct()
    {
        $this->mail = new PHPMailer();
    }

    public function set_config($config){
        $this->mail->IsSMTP(); // telling the class to use SMTP
        $this->mail->CharSet = "utf-8";                  // 一定要設定 CharSet 才能正确处理中文
        $this->mail->SMTPDebug = 0;                     // enables SMTP debug information
        $this->mail->SMTPAuth = true;                  // enable SMTP authentication
        $this->mail->SMTPSecure = $config['smtp_secure'];                 // sets the prefix to the servier
        $this->mail->Host = $config['server'];      // sets GMAIL as the SMTP server
        $this->mail->Port = $config['port'];                   // set the SMTP port for the GMAIL server
        $this->mail->Username = $config['sender'];
        $this->mail->Password = $config['secret_key'];
        $this->mail->AddReplyTo($config['sender']);
        $this->mail->SetFrom($config['sender']);
        $this->mail->isHTML(true);
    }

    public function add_recipient($recipient){
        $this->mail->AddAddress($recipient);
    }

    /**
     * 发送邮件
     * @param $recipient
     * @param $subject
     * @param $content
     * @param null $attachments
     * @return bool
     */
    public function send_email($recipient,$subject,$content,$attachments=null){
        try{
            if($recipient) {
                $this->mail->AddAddress($recipient);
            }
            $this->mail->Subject = $subject;
            $this->mail->Body    = $content;
            if($attachments){
                if(is_array($attachments)){
                    foreach($attachments as $k=>$val){
                        $this->mail->addAttachment($val);
                    }
                }else{
                    $this->mail->addAttachment($attachments);
                }
            }
            if($this->mail->Send()) {
                return true;
            }else{
                show_error($this->mail->ErrorInfo);
                return false;
            }
        } catch (phpmailerException $e) {
            show_error($e->errorMessage(),500); //Pretty error messages from PHPMailer
        } catch (Exception $e) {
            show_error($e->getMessage(),500); //Boring error messages from anything else!
        }
    }
}