c# - 如何使用 C# 通过 Gmail 发送电子邮件

Question

尝试通过网络服务发送电子邮件时出现错误。我尝试启用对安全性较低的应用程序的访问，禁用两步验证并通过网络浏览器登录帐户。 SO 上的所有解决方案都不适合我。我仍然得到:

Error: System.Net.Mail.SmtpException: The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required.

我该怎么做才能解决这个问题？

namespace EmailService
{
    public class Service1 : IService1
    {    
        public string SendEmail(string inputEmail, string subject, string body)
        {
            string returnString = "";
            try
            {
                MailMessage email = new MailMessage();
                SmtpClient smtp = new SmtpClient();
                smtp.Host = "smtp.gmail.com";

                // set up the Gmail server
                smtp.EnableSsl = true;
                smtp.Port = 587;
                smtp.Credentials = new System.Net.NetworkCredential("myemail@gmail.com", "mypassword");
                smtp.DeliveryMethod = SmtpDeliveryMethod.Network;
                smtp.UseDefaultCredentials = false;

                // draft the email
                MailAddress fromAddress = new MailAddress("cse445emailservice@gmail.com");
                email.From = fromAddress;
                email.To.Add(inputEmail);
                email.Subject = body;
                email.Body = body;

                smtp.Send(email);

                returnString = "Success! Please check your e-mail.";
            }
            catch(Exception ex)
            {
                returnString = "Error: " + ex.ToString();
            }
            return returnString;
        }
    }
}

Answer 1

就到这里:Less secure apps , 使用您在 c# 代码中用于发送邮件的电子邮件和密码登录，然后选择 Turn On。

另请转到此链接并单击继续 Allow access to your Google account

我也稍微编辑了一下:

public string sendit(string ReciverMail)
{
    MailMessage msg = new MailMessage();

    msg.From = new MailAddress("YourMail@gmail.com");
    msg.To.Add(ReciverMail);
    msg.Subject = "Hello world! " + DateTime.Now.ToString();
    msg.Body = "hi to you ... :)";
    SmtpClient client = new SmtpClient();
    client.UseDefaultCredentials = true;
    client.Host = "smtp.gmail.com";
    client.Port = 587;
    client.EnableSsl = true;
    client.DeliveryMethod = SmtpDeliveryMethod.Network;
    client.Credentials = new NetworkCredential("YourMail@gmail.com", "YourPassword");
    client.Timeout = 20000;
    try
    {
       client.Send(msg);
        return "Mail has been successfully sent!";
    }
    catch (Exception ex)
    {
        return "Fail Has error" + ex.Message;
    }
    finally
    {
       msg.Dispose();
    }
}

如果上面的代码不行，试试改成下面的代码:

    SmtpClient client = new SmtpClient();
    client.Host = "smtp.gmail.com";
    client.Port = 587;
    client.EnableSsl = true;
    client.DeliveryMethod = SmtpDeliveryMethod.Network;
    client.UseDefaultCredentials = false;
    client.Credentials = new NetworkCredential("YourMail@gmail.com", "YourPassword");