刚看到一个博文，是c#实现gmial邮件发送 的文章，前几天我也写了一个，发出来分享下！
后台设置如图：

using System;
using System.Collections.Generic;
using System.Text;
using System.Net.Mail;

public static class EmailManager
{
    /// <summary>
    /// 发送Email
    /// </summary>
    /// <param name="fromto">发件人</param>
    /// <param name="title">标题</param>
    /// <param name="content">内容</param>
    public static void sendMail(string fromto, string title, string content)
    {
        SMTPSettingManager SSM = new SMTPSettingManager();
        SMTPSetting ss = SSM.DSmtp();//反序列化配置

        string[] mailTo = fromto.Split(',');// 分割收件人地址

        MailAddress from = new MailAddress(ss.EmailFrom); //发件人地址
        MailMessage message = new MailMessage();
        message.From = from; //添加发件人地址
        for (int i = 0; i < mailTo.Length; i++) //循环添加收件人地址
        {
            message.To.Add(mailTo[i]);
        }
        message.Subject = title; //标题
        message.Body = content; //内容
        message.BodyEncoding = Encoding.Default; //内容编码
        message.IsBodyHtml = true; //指定为html页面
        message.SubjectEncoding = Encoding.Default; //主题编码
        SmtpClient client = new SmtpClient(ss.SMTP);
        client.Credentials = new System.Net.NetworkCredential(ss.SMTPUser, ss.SMTPPassword); //用户名和密码

        if (ss.IsSSL) //安全连接
        {
            client.EnableSsl = true;
        }
        client.Port = Convert.ToInt32(ss.Port);//端口
        client.Send(message); //发送

    }
}