Using C#, how to retrieve list of emails from Gmail server via POP3

Question

Hy,

I have an application that sends mails with Gmail SMTP server (smtp.gmail.com) using SSL.

Now I want to read the emails from that account, does anyone have any idea how can I make this programatically in C# and ASP.NET?

At this point I'm using this code:

TcpClient tcpClient = new TcpClient();
tcpClient.Connect("pop.gmail.com", 587);

NetworkStream netStream = tcpClient.GetStream();
System.IO.StreamReader strReader = new System.IO.StreamReader(netStream);

Label7.Text = strReader.ReadLine() + "<br />"; 
//Label7.Text = "Server connected!";

byte[] WriteBuffer = new byte[1024];
ASCIIEncoding enc = new System.Text.ASCIIEncoding();

WriteBuffer = enc.GetBytes("USER " + TextBox4.Text + "\r\n");
netStream.Write(WriteBuffer, 0, WriteBuffer.Length);
Label7.Text += strReader.ReadLine() + "<br />";

WriteBuffer = enc.GetBytes("PASS " + TextBox5.Text + "\r\n");
netStream.Write(WriteBuffer, 0, WriteBuffer.Length);
Label7.Text += strReader.ReadLine() + "<br />";

WriteBuffer = enc.GetBytes("LIST\r\n");
netStream.Write(WriteBuffer, 0, WriteBuffer.Length);

String ListMessage;
while (true)
{
    ListMessage = strReader.ReadLine();
    if (ListMessage == ".")
    {
        break;
    }
    else
    {
        Label7.Text += ListMessage + "<br />";
        continue;
    }
}

WriteBuffer = enc.GetBytes("QUIT\r\n");
netStream.Write(WriteBuffer, 0, WriteBuffer.Length);
Label7.Text += strReader.ReadLine() + "<br />"; 

And when I debug it it's shows that it's connected but no response in retrieving emails.

Answer 1

I´m using this sample library that appeared at The Code Project link text that has a nice and clean api to work with pop3.

Answer 2

POP3 features of this open source project (I'm involved in) contains everything you need. Including secure communications support & advanced authentication.

If you really want to do one yourself, browsing the source code will probably save you days of development.

Answer 3

@Pierre 303

Thanks for the refference.

I have this code now:

        Pop3Client pop = new Pop3Client();
        try
        {
            Label7.Text = string.Format("Connection to the pop 3 server : {0}", "pop.gmail.com");
            pop.ConnectSsl("pop.gmail.com", 995, TextBox4.Text, TextBox5.Text);
            Label7.Text += string.Format("Message Count: {0}", pop.MessageCount.ToString());
            if (pop.MessageCount > 0)
            {
                Header msgHeader = pop.RetrieveHeaderObject(1);

                Label7.Text += string.Format("Subject: {0} From :{1} Date Sent {2}", msgHeader.Subject, msgHeader.From.Email, msgHeader.DateString);
            }
        }

        catch (Pop3Exception pexp)
        {
            Label7.Text = string.Format("Pop3 Error: {0}", pexp.Message);
        }

        catch (Exception ex)
        {
            Label7.Text = string.Format("Failed: {0}", ex.Message);
        }

        finally
        {
            if (pop.IsConnected)
            {
                pop.Disconnect();
            }
        }

I'm not getting any error but the message count it's 0... and I have probably 100 mails in my inbox...

I'm missing something?