C# 邮件发送帮助类。

由于工作需要，实现了邮件帮助类，自己测试通过，仅供参考。

using System;
using System.Net;
using System.Net.Mail;
using System.Text;
namespace EmailSender.CommonContract
{
public class EmailSender
   {
          private readonly string _smtpHost;
          private readonly int _smtpPort;
          private readonly string _smtpUsername;
          private readonly string _smtpPassword;
        
        /// <summary>
        /// 邮箱验证构造函数
        /// </summary>
        /// <param name="smtpHost">邮件服务器</param>
        /// <param name="smtpPort">端口</param>
        /// <param name="smtpUsername">用户名</param>
        /// <param name="smtpPassword">QQ邮箱POP3/SMTP服务的授权码</param>
        public EmailSender(string smtpHost, int smtpPort, string smtpUsername, string smtpPassword)
        {
            _smtpHost = smtpHost;
            _smtpPort = smtpPort;
            _smtpUsername = smtpUsername;
            _smtpPassword = smtpPassword;
        }
     
/// <summary>
/// 邮件发送
/// </summary>
/// <param name="mailTo">收件人邮箱，例456@qq.com</param>
/// <param name="subject">邮件标题</param>
/// <param name="body"> 邮件内容</param>
/// <param name="errMsg"> 输出错误消息</param>
/// <returns></returns>
public bool SendMail(string mailTo, string subject, string body,out string errMsg)
{
          // 邮件服务设置
          SmtpClient smtpClient = new SmtpClient();
          // 指定电子邮件发送方式
          smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network;
          // 指定SMTP服务器
          smtpClient.Host = _smtpHost;
          //指定SMTP服务器端口
          smtpClient.Port = _smtpPort;
          // 使用安全加密连接（是否启用SSL）
          smtpClient.EnableSsl = true;
          // 不和请求一块发送。
          smtpClient.UseDefaultCredentials = false;
          // 用户名和密码
          smtpClient.Credentials = new NetworkCredential(_smtpUsername, _smtpPassword);
          // 发送人和收件人
          MailMessage mailMessage = new MailMessage(_smtpUsername, mailTo);
          // 主题
          mailMessage.Subject = subject;
          // 内容
          mailMessage.Body = body;
          // 正文编码
          mailMessage.BodyEncoding = Encoding.UTF8;
          // 设置为HTML格式
          mailMessage.IsBodyHtml = true;
          // 优先级
          mailMessage.Priority = MailPriority.Low;
          try
          {
          // 发送邮件
          smtpClient.Send(mailMessage);
          errMsg = "";
          return true;
          }
          catch (SmtpException ex)
          {
          //返回错误
          errMsg= "邮件发送异常,"+ex.ToString();
          return false;
          }
		}
	}
}

调用实例：
EmailSender send = new EmailSender("smtp.qq.com",587, "发件人邮箱地址", "密码=授权码");
string errMsg = "";//输出错误信息
send.SendMail("收件人地址","主题","发送内容",out errMsg)

本人测试通过，上图是发送成功截图！！