Question

    using System;
    using System.IO;
    using System.Net;
    using System.Net.Mail;
    using System.Net.Mime;
    using System.Text;

    namespace AzureSendGridDemo
    {
        class Program
        {
            static void Main(string[] args)
            {
                MailMessage msg = new MailMessage();
                msg.From = new MailAddress("FromAddress", "Name");
                msg.To.Add(new MailAddress("ToAddress", "Name"));
                msg.Subject = "Mail from Azure and SendGrid!";
                msg.Body = "This is just a simple test message!";
                msg.IsBodyHtml = true;
                msg.Attachments.Add("D:\image.jpg"); // if i put local path, it works.
                msg.Attachments.Add(new Attachment(@"https://images-na.ssl-images-amazon.com/images/I/71nTxKhiqrL._UL1500_.jpg")); // if i put global path it doesn't works. It shows some errors are shown below:  
//Sendgrid credentials for sending mail using smtpclient wrapper class.
                SmtpClient client = new SmtpClient("smtp.sendgrid.net", 587);
                client.DeliveryMethod = SmtpDeliveryMethod.Network;
                client.EnableSsl = true;
                client.UseDefaultCredentials = false;
                client.Credentials = new System.Net.NetworkCredential("Username", "Password");
                client.Send(msg);
                Console.Read();
            }
        }
    }

如果我使用的是全局路径，则会在我的控制台应用程序中显示错误：

未处理的异常：System.NotSupportedException：不支持给定路径的格式。在System.IO.Path.GetFullPath（String path）在System.IO.FileStream..ctor（字符串路径，FileMode模式，FileAccess访问，FileShare共享，Int32 bufferSize，FileOptions选项）在System.IO.FileStream..ctor（字符串路径，FileMode模式，FileAccess访问，FileShare共享）在System.Net.Mail.AttachmentBase.SetContentFromFile（String fileName，String mediaType）在System.Net.Mail.AttachmentBase..ctor（String fileName）在System.Net.Mail.Attachment..ctor（String fileName）在E：\ SendGrid \ AzureSendGridDemo \ AzureSendGridDemo \ Program.cs中的AzureSendGridDemo.Program.Main（String [] args）：第41行按任意键继续。。

Answer 1

这是因为您无法将URL传递给附件等电子邮件。

URL是您可以放在邮件正文中的链接，或者您也可以使用WebClient类C＃下载文档并将其附加到电子邮件中。

Answer 2

Attachment构造函数没有重载，允许您传递url字符串。虽然有一个接受Stream，但你可以这样做......

var imageRequest = HttpWebRequest.Create("https://images-na.ssl-images-amazon.com/images/I/71nTxKhiqrL._UL1500_.jpg")
using (var imageStream = imageRequest.GetResponse().GetResponseStream())
{
    var x = new Attachment(imageStream, "image/jpeg");
}

如何发送带有全局附件的邮件？

2 个答案: