C#实现发送邮件的方法

#region 发送邮件部分
    private static String fromMail = "1111@126.com";  ///邮箱名称
    private static String mailPwd = "111111";     ///密码
    private static string toMail = "2222@163.com";  ///邮箱服务器
    private static string fileStr;//当前图片路径，在添加附件时用
    /// 

    /// 发送邮件
    /// 
    /// 附件地址，以~分
    /// 是否发送截屏
    /// 
    public static string SendMail(string fileUrl, string screen)
    {
     
      MailAddress from = new MailAddress(fromMail);
      MailAddress to = new MailAddress(toMail);

      MailMessage message = new MailMessage(from, to);
      message.Subject = "M邮件 " +11111;//主题
      message.SubjectEncoding = System.Text.Encoding.UTF8;

      Attachment attachFile = new Attachment(fileStr);
      if (screen == "True")
        message.Attachments.Add(attachFile);

      string[] files = fileUrl.Split('~');
      for (int i = 0; i