Pourquoi est-ce que «la propriété ne peut pas être affectée» s'affiche lors de l'envoi d'un e-mail SMTP?

Je ne comprends pas pourquoi ce code ne fonctionne pas. Je reçois une erreur indiquant que la propriété ne peut pas être affectée

MailMessage mail = new MailMessage();
SmtpClient client = new SmtpClient();            
client.Port = 25;
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.UseDefaultCredentials = false;
client.Host = "smtp.gmail.com";
mail.To = "user@hotmail.com"; // <-- this one
mail.From = "you@yourcompany.com";
mail.Subject = "this is a test email.";
mail.Body = "this is my test email body";
client.Send(mail);

mail.Toet mail.Fromsont en lecture seule. Déplacez-les vers le constructeur.

using System.Net.Mail;

...

MailMessage mail = new MailMessage("you@yourcompany.com", "user@hotmail.com");
SmtpClient client = new SmtpClient();
client.Port = 25;
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.UseDefaultCredentials = false;
client.Host = "smtp.gmail.com";
mail.Subject = "this is a test email.";
mail.Body = "this is my test email body";
client.Send(mail);

Ce :

mail.To = "user@hotmail.com";

Devrait être:

mail.To.Add(new MailAddress("user@hotmail.com"));

J'ai enfin réussi à travailler :)

using System.Net.Mail;
using System.Text;

...

// Command line argument must the the SMTP host.
SmtpClient client = new SmtpClient();
client.Port = 587;
client.Host = "smtp.gmail.com";
client.EnableSsl = true;
client.Timeout = 10000;
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.UseDefaultCredentials = false;
client.Credentials = new System.Net.NetworkCredential("user@gmail.com","password");

MailMessage mm = new MailMessage("donotreply@domain.com", "sendtomyemail@domain.co.uk", "test", "test");
mm.BodyEncoding = UTF8Encoding.UTF8;
mm.DeliveryNotificationOptions = DeliveryNotificationOptions.OnFailure;

client.Send(mm);

désolé pour une mauvaise orthographe avant

public static void SendMail(MailMessage Message)
{
    SmtpClient client = new SmtpClient();
    client.Host = "smtp.googlemail.com";
    client.Port = 587;
    client.UseDefaultCredentials = false;
    client.DeliveryMethod = SmtpDeliveryMethod.Network;
    client.EnableSsl = true;
    client.Credentials = new NetworkCredential("myemail@gmail.com", "password");
    client.Send(Message); 
}

Voilà comment cela fonctionne pour moi. J'espère que vous le trouverez utile

MailMessage objeto_mail = new MailMessage();
SmtpClient client = new SmtpClient();
client.Port = 25;
client.Host = "smtp.internal.mycompany.com";
client.Timeout = 10000;
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.UseDefaultCredentials = false;
client.Credentials = new System.Net.NetworkCredential("user", "Password");
objeto_mail.From = new MailAddress("from@server.com");
objeto_mail.To.Add(new MailAddress("to@server.com"));
objeto_mail.Subject = "Password Recover";
objeto_mail.Body = "Message";
client.Send(objeto_mail);

Tout d' abord aller à https://myaccount.google.com/lesssecureapps et faire Permettre des applications moins sécurisées vrai .

Utilisez ensuite le code ci-dessous. Ce code ci-dessous ne fonctionnera que si votre adresse e-mail de provenance provient de gmail.

static void SendEmail()
    {
        string mailBodyhtml =
            "<p>some text here</p>";
        var msg = new MailMessage("from@gmail.com", "to1@gmail.com", "Hello", mailBodyhtml);
        msg.To.Add("to2@gmail.com");
        msg.IsBodyHtml = true;
        var smtpClient = new SmtpClient("smtp.gmail.com", 587); //**if your from email address is "from@hotmail.com" then host should be "smtp.hotmail.com"**
        smtpClient.UseDefaultCredentials = true;
        smtpClient.Credentials = new NetworkCredential("from@gmail.com", "password");
        smtpClient.EnableSsl = true;
        smtpClient.Send(msg);
        Console.WriteLine("Email Sent Successfully");
    }

Si vous souhaitez que votre e-mail et votre mot de passe n'apparaissent pas dans votre code et que le serveur client de messagerie de votre entreprise utilise vos informations d'identification Windows ci-dessous.

client.Credentials = CredentialCache.DefaultNetworkCredentials;

La source

Cela a juste fonctionné pour moi en mars 2017. A commencé avec la solution ci-dessus "Enfin, ça a fonctionné :)" qui n'a pas fonctionné au début.

SmtpClient client = new SmtpClient();
client.Port =  587;
client.Host = "smtp.gmail.com";
client.EnableSsl = true;
client.Timeout = 10000;
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.UseDefaultCredentials = false;
client.Credentials = new System.Net.NetworkCredential("<me>@gmail.com", "<my pw>");
MailMessage mm = new MailMessage(from_addr_text, to_addr_text, msg_subject, msg_body);
mm.BodyEncoding = UTF8Encoding.UTF8;
mm.DeliveryNotificationOptions = DeliveryNotificationOptions.OnFailure;

client.Send(mm);

Cette réponse comprend:

• Utilisation de «using» dans la mesure du possible ( interfaces IDisposable )
• Utilisation des initialiseurs d'objets
• Programmation asynchrone
• Extraire SmtpConfig vers une classe externe (l'adapter à vos besoins)

Voici le code extrait:

    public async Task SendAsync(string subject, string body, string to)
    {
        using (var message = new MailMessage(smtpConfig.FromAddress, to)
        {
            Subject = subject,
            Body = body,
            IsBodyHtml = true
        })
        {
            using (var client = new SmtpClient()
            {
                Port = smtpConfig.Port,
                DeliveryMethod = SmtpDeliveryMethod.Network,
                UseDefaultCredentials = false,
                Host = smtpConfig.Host,
                Credentials = new NetworkCredential(smtpConfig.User, smtpConfig.Password),
            })
            {
                await client.SendMailAsync(message);
            }
        }                                     
    }

Classe SmtpConfig:

public class SmtpConfig
{
    public string Host { get; set; }
    public string User { get; set; }
    public string Password { get; set; }
    public int Port { get; set; }
    public string FromAddress { get; set; }
}

MailMessage mm = new MailMessage(txtEmail.Text, txtTo.Text);
mm.Subject = txtSubject.Text;
mm.Body = txtBody.Text;
if (fuAttachment.HasFile)//file upload select or not
{
    string FileName = Path.GetFileName(fuAttachment.PostedFile.FileName);
    mm.Attachments.Add(new Attachment(fuAttachment.PostedFile.InputStream, FileName));
}
mm.IsBodyHtml = false;
SmtpClient smtp = new SmtpClient();
smtp.Host = "smtp.gmail.com";
smtp.EnableSsl = true;
NetworkCredential NetworkCred = new NetworkCredential(txtEmail.Text, txtPassword.Text);
smtp.UseDefaultCredentials = true;
smtp.Credentials = NetworkCred;
smtp.Port = 587;
smtp.Send(mm);
Response.write("Send Mail");

Voir la vidéo: https://www.youtube.com/watch?v=bUUNv-19QAI

smtp.Host = "smtp.gmail.com"; // the host name
smtp.Port = 587; //port number
smtp.EnableSsl = true; //whether your smtp server requires SSL
smtp.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network;
smtp.Credentials = new NetworkCredential(fromAddress, fromPassword);
smtp.Timeout = 20000;

Parcourez cet article pour plus de détails

Il suffit d'essayer ceci:

string smtpAddress = "smtp.gmail.com";
int portNumber = 587;
bool enableSSL = true;
string emailFrom = "companyemail";
string password = "password";
string emailTo = "Your email";
string subject = "Hello!";
string body = "Hello, Mr.";
MailMessage mail = new MailMessage();
mail.From = new MailAddress(emailFrom);
mail.To.Add(emailTo);
mail.Subject = subject;
mail.Body = body;
mail.IsBodyHtml = true;
using (SmtpClient smtp = new SmtpClient(smtpAddress, portNumber))
{
   smtp.Credentials = new NetworkCredential(emailFrom, password);
   smtp.EnableSsl = enableSSL;
   smtp.Send(mail);
}

MailKit est une bibliothèque cliente mail multiplateforme Open Source basée sur MimeKit et optimisée pour les appareils mobiles. Il a plus de fonctionnalités avancées que le support System.Net.Mail Microsoft TNEF via MimeKit.

Téléchargez le paquet nuget ici .

Voir cet exemple, vous pouvez envoyer du courrier

            MimeMessage mailMessage = new MimeMessage();
            mailMessage.From.Add(new MailboxAddress(senderName, sender@address.com));
            mailMessage.Sender = new MailboxAddress(senderName, sender@address.com);
            mailMessage.To.Add(new MailboxAddress(emailid, emailid));
            mailMessage.Subject = subject;
            mailMessage.ReplyTo.Add(new MailboxAddress(replyToAddress));
            mailMessage.Subject = subject;
            var builder = new BodyBuilder();
            builder.TextBody = "Hello There";            
            try
            {
                using (var smtpClient = new SmtpClient())
                {
                    smtpClient.Connect("HostName", "Port", MailKit.Security.SecureSocketOptions.None);
                    smtpClient.Authenticate("user@name.com", "password");

                    smtpClient.Send(mailMessage);
                    Console.WriteLine("Success");
                }
            }
            catch (SmtpCommandException ex)
            {
                Console.WriteLine(ex.ToString());              
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());                
            }

envoyer un e-mail par smtp

public void EmailSend(string subject, string host, string from, string to, string body, int port, string username, string password, bool enableSsl)
    {
        try
        {
            MailMessage mail = new MailMessage();
            SmtpClient smtpServer = new SmtpClient(host);
            mail.Subject = subject;
            mail.From = new MailAddress(from);
            mail.To.Add(to);
            mail.Body = body;
            smtpServer.Port = port;
            smtpServer.Credentials = new NetworkCredential(username, password);
            smtpServer.EnableSsl = enableSsl;
            smtpServer.Send(mail);
        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message);
        }
    }

Initialisez l' MailMessageadresse e-mail de l'expéditeur et du destinataire. Cela devrait être quelque chose comme

string from = "codeforwin@gmail.com";  //Senders email   
string to = "reciever@gmail.com";  //Receiver's email  
MailMessage msg = new MailMessage(from, to); 

Lire l'extrait de code complet sur la façon d'envoyer des e-mails en c #

cela fonctionnerait aussi ..

string your_id = "your_id@gmail.com";
string your_password = "password";
try
{
   SmtpClient client = new SmtpClient
   {
     Host = "smtp.gmail.com",
     Port = 587,
     EnableSsl = true,
     DeliveryMethod = SmtpDeliveryMethod.Network,
     Credentials = new System.Net.NetworkCredential(your_id, your_password),
     Timeout = 10000,
   };
   MailMessage mm = new MailMessage(your_iD, "recepient@gmail.com", "subject", "body");
   client.Send(mm);
   Console.WriteLine("Email Sent");
 }
 catch (Exception e)
 {
   Console.WriteLine("Could not end email\n\n"+e.ToString());
 }

 //Hope you find it useful, it contain too many things

    string smtpAddress = "smtp.xyz.com";
    int portNumber = 587;
    bool enableSSL = true;
    string m_userName = "support@xyz.com";
    string m_UserpassWord = "56436578";

    public void SendEmail(Customer _customers)
    {
        string emailID = gghdgfh@gmail.com;
        string userName = DemoUser;

        string emailFrom = "qwerty@gmail.com";
        string password = "qwerty";
        string emailTo = emailID;

        // Here you can put subject of the mail
        string subject = "Registration";
        // Body of the mail
        string body = "<div style='border: medium solid grey; width: 500px; height: 266px;font-family: arial,sans-serif; font-size: 17px;'>";
        body += "<h3 style='background-color: blueviolet; margin-top:0px;'>Aspen Reporting Tool</h3>";
        body += "<br />";
        body += "Dear " + userName + ",";
        body += "<br />";
        body += "<p>";
        body += "Thank you for registering </p>";            
        body += "<p><a href='"+ sURL +"'>Click Here</a>To finalize the registration process</p>";
        body += " <br />";
        body += "Thanks,";
        body += "<br />";
        body += "<b>The Team</b>";
        body += "</div>";
       // this is done using  using System.Net.Mail; & using System.Net; 
        using (MailMessage mail = new MailMessage())
        {
            mail.From = new MailAddress(emailFrom);
            mail.To.Add(emailTo);
            mail.Subject = subject;
            mail.Body = body;
            mail.IsBodyHtml = true;
            // Can set to false, if you are sending pure text.

            using (SmtpClient smtp = new SmtpClient(smtpAddress, portNumber))
            {
                smtp.Credentials = new NetworkCredential(emailFrom, password);
                smtp.EnableSsl = enableSSL;
                smtp.Send(mail);
            }
        }
    }