客户端错误。SendAsync

Question

我尝试根据代码发送电子邮件：

http://msdn.microsoft.com/es-es/library/system.net.mail.smtpclient(v=vs.110).aspx

Sending email in .NET through Gmail

所以我做到了：

SmtpClient client = new SmtpClient("smtp.gmail.com",587);
MailAddress from = new MailAddress("xxx@gmail.com","Jane " + (char)0xD8 + " Clayton",System.Text.Encoding.UTF8);
MailAddress to = new MailAddress("yyy@gmail.com");
MailMessage message = new MailMessage(from, to);
message.Body = "This is a test e-mail message sent by an application. ";
string someArrows = new string(new char[] { '\u2190', '\u2191', '\u2192', '\u2193' });
message.Body += Environment.NewLine + someArrows;
message.BodyEncoding = System.Text.Encoding.UTF8;
message.Subject = "test message 1" + someArrows;
message.SubjectEncoding = System.Text.Encoding.UTF8;
client.SendCompleted += new SendCompletedEventHandler(SendCompletedCallback);
string userState = "test message1";
client.SendAsync(message, userState);
Console.WriteLine("Sending message... press c to cancel mail. Press any other key to exit.");
string answer = Console.ReadLine();
if (answer.StartsWith("c") && mailSent == false)
{
    client.SendAsyncCancel();
}
message.Dispose();
Console.WriteLine("Goodbye.");
return View();

但在“client.SendAsync(message, userState);”行出现问题 和错误说：

System.dll 中的“System.Net.Mail.SmtpException”类型的未处理异常，但未在用户代码中处理。

附加信息：发送邮件时出错。

我该如何解决它？？

Answer 1

Gmail 需要 SSL 连接。

将EnableSsl 设置为真。

Answer 2

首先将您的代码保留在 try catch 块内 -

.....//other codes

try{

    client.SendAsync(message, userState);

}
catch(Exception e){
    //add a breakpoint here to see what is the error
}

然后，在 catch 块内添加一个断点并开始调试以查看错误/异常是什么。通常大多数异常都包含修复它的说明。所以你找到了错误，你就找到了解决方案。

Answer 3

最后我改变了我的代码类似于>>

            System.Net.Mail.MailMessage msg = new System.Net.Mail.MailMessage();
            msg.To.Add("RecipientMail");
            msg.From = new MailAddress("sender@gmail.com", "gmailpassword", System.Text.Encoding.UTF8);
            msg.Subject = "UR SUBJECT";
            msg.SubjectEncoding = System.Text.Encoding.UTF8;
            msg.Body = "UR BODY";
            msg.BodyEncoding = System.Text.Encoding.UTF8;
            msg.IsBodyHtml = false;

            //Aquí es donde se hace lo especial
            SmtpClient client = new SmtpClient();
            client.Credentials = new System.Net.NetworkCredential("sender@gmail.com", "gmailpassword");
            client.Port = 587;
            client.Host = "smtp.gmail.com";
            client.EnableSsl = true; //Esto es para que vaya a través de SSL que es obligatorio con GMail
            try
            {
                client.Send(msg);
            }
            catch (System.Net.Mail.SmtpException ex)
            {
                Console.WriteLine(ex.Message);
                Console.ReadLine();
            }

并在此页面中设置我的 gmail 帐户>> https://www.google.com/settings/security/lesssecureapps

感谢大家的帮助！！