无法在c#中发送带有excel附件的邮件

Question

我正在尝试发送带有 excel 附件的邮件，邮件正在发送，但附件在 filename.xlsx.txt 中，没有内容（空白 .txt 文件）

    public void SendEmail()
    {
        MailMessage mail = new MailMessage();
        SmtpClient SmtpServer = new SmtpClient("smtp.test.net");
        mail.From = new MailAddress("test@test.com");
        mail.To.Add("test@test.com");
        mail.Subject = "Test Mail - 1";
        mail.Body = "mail with attachment";


        Attachment attachment;
        attachment = new Attachment(File.Open(AppDomain.CurrentDomain.BaseDirectory + "result.xlsx", FileMode.Open), "result.xlsx");
        attachment.ContentType = new ContentType("application/vnd.ms-excel");
        mail.Attachments.Add(attachment);

        SmtpClient client = new SmtpClient("smtp.test.net");
        client.DeliveryMethod = SmtpDeliveryMethod.Network;
        NetworkCredential credetial = new NetworkCredential("test@test.com", "******", "test.com");
        client.UseDefaultCredentials = true;
        client.EnableSsl = true;
        try
        {
            System.Threading.Thread.Sleep(5000);
            client.Send(mail);
        }
        catch (Exception e)
        {

        }

    }

电子邮件附件：

Answer 1

您实际上并没有附加文件，而是打开文件并将其保存为result.xlsx，保存时默认为.txt 扩展名。这就解释了为什么你会收到result.xlsx.txt

代替

Attachemnt attachment = new Attachment(File.Open(AppDomain.CurrentDomain.BaseDirectory + "result.xlsx", FileMode.Open), "result.xlsx");
attachment.ContentType = new ContentType("application/vnd.ms-excel");

使用

message.Attachments.Add(new Attachment(PathToAttachment));

只需传递文件的路径即可。

再次不确定您是否需要内容类型位。

Answer 2

我有一个像这样附加的电子表格... （使用您的对象名称“mail”）

mail.Attachments.Add(new Attachment(mail, "result.xls", "application/vnd.ms-excel"));

代替：

Attachment attachment;
attachment = new Attachment(File.Open(AppDomain.CurrentDomain.BaseDirectory + "result.xlsx", FileMode.Open), "result.xlsx");
attachment.ContentType = new ContentType("application/vnd.ms-excel");
mail.Attachments.Add(attachment);