c# - 发送电子邮件 - 错误

Question

我正在尝试使用 Winforms 应用程序中的以下代码发送电子邮件。用户名和密码正确且真实 - 但已在代码中屏蔽。

我不知道我的本地机器是否有能力发送电子邮件？

但是请告诉我，我需要什么来查看我的机器配置(在 IIS 中)？

错误:“无法建立连接，因为目标机器主动拒绝它 209.85.143.109:587”

//All Variable Declarations
String senderAddress = string.Empty;
String receiveraddress = string.Empty;
String emailSubject = string.Empty;
String emailMessageText = string.Empty;
MailMessage mail = new MailMessage();
SmtpClient client = new SmtpClient("smtp.gmail.com",587);


private void btnEmail_Click(object sender, EventArgs e)
{

      try
      {
            //Get the Values of Controls

            senderAddress = txtSenderEmail.Text;
            receiveraddress = txtReceiverEmail.Text;
            emailSubject = txtSubject.Text;
            emailMessageText = txtMessageBody.Text;

            //Pass the Values
            mail.From = new MailAddress(senderAddress, "xxxxxxxxxx", System.Text.Encoding.UTF8);
            mail.To.Add(receiveraddress);
            mail.Subject = emailSubject;
            mail.Body = emailMessageText;
            client.UseDefaultCredentials = false;
            client.Credentials = new NetworkCredential("xxxxxxx@gmail.com", "xxxxxx");
            client.EnableSsl = true;
            client.Send(mail);
            System.Windows.Forms.MessageBox.Show("Email Sent Successfully");



      }
      catch (Exception mailException)
      {
            System.Windows.Forms.MessageBox.Show("Message Not Sent ,Error:   " + mailException.Message);
            throw;
      }
      finally
      {

      }



}

我已经为两个端口完成了 telnet，出现的错误是:无法打开与主机的连接。

请看下面的图片，它应该会让你更清楚，

Answer 1

GMail requires you to use SSL .您需要用于 TLS/STARTTLS 的端口是 587。对于 SSL，它是 465。下面是您可以用来通过命令行发送电子邮件的代码。 CommandLine.Utility可以在 CodeProject 下载。

using System;
using System.Collections.Generic;
using System.Text;
using System.Net;
using System.Net.Mail;
using System.Net.Mime;
using System.ComponentModel;
using CommandLine.Utility;

namespace SmtpClientProgram
{
    class Program
    {        

        static void Main(string[] args)
        {
            Arguments cmdLine = new Arguments(args);        

            SmtpClient mailer = new SmtpClient();

            // --ssl means we are using SSL/TLS

            mailer.EnableSsl = Convert.ToBoolean(cmdLine["ssl"]);

            // -host=smtp.gmail.com

            if (cmdLine["host"] != null)
                mailer.Host = cmdLine["host"];
            else
            {
                Console.WriteLine("Hostname must be specified");
                return;
            }

            // -port=25

            if (cmdLine["port"] != null)
                try
                {
                    mailer.Port = Convert.ToInt32(cmdLine["port"]);
                }
                catch (Exception)
                {
                    Console.WriteLine("Port must be a number between 1 and 65535");
                }
            else
                mailer.Port = 25;

            // -user= -password=
            if (cmdLine["user"] != null && cmdLine["password"] != null)
            {                
                mailer.Credentials = new NetworkCredential(cmdLine["user"], cmdLine["password"]);
            }

            try
            {
                MailMessage mail = new MailMessage();

                mail.From = new MailAddress(cmdLine["from"], cmdLine["name"]);

                if (cmdLine["to1"] != null)
                    mail.To.Add(cmdLine["to1"]);
                else
                    Console.WriteLine("Must specify first TO address");

                if (cmdLine["to2"] != null)
                    mail.To.Add(cmdLine["to2"]);

                if (cmdLine["to3"] != null)
                    mail.To.Add(cmdLine["to3"]);

                if (cmdLine["subject"] != null)
                    mail.Subject = cmdLine["subject"];

                if (cmdLine["body"] != null)
                    mail.Body = cmdLine["body"];

                mailer.Send(mail);

                //mailer.Send(cmdLine["from"], cmdLine["to"], cmdLine["subject"], cmdLine["body"]);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
                return;
            }
            Console.WriteLine("Success");            
        }
    }
}

编辑:如果您无法连接到端口 587(服务可能已关闭)，请尝试使用 SSL 的 465 或使用 SSL 的 25。参见 here for Gmail help on sending email .