Retrieve Email from IMAP4 server in C#

In previous section, I introduced retrieving email from POP3 server in C#. In this section, I will introduce the IMAP4 server.

Introduction

IMAP4 protocol is different with POP3 protocol. First of all, IMAP4 supports retrieving email from different mail folder and folder management. Secondly, IMAP4 supports mail flags management. Therefore, we can do more things with IMAP4 server. To better understand the IMAP4 protocol, please see the following examples.

Note

Remarks: All of examples in this section are based on first section: A simple C# project. To compile and run the following example codes successfully, please click here to learn how to create the test project and add reference to your project.

[C# Example - Retrieve email from IMAP4 inbox]

The following example codes demonstrate how to download email from IMAP4 server default mailbox. In order to run it correctly, please change email server, user, password, folder, file name values.

Note

To get the full sample projects, please refer to Samples section.

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using EAGetMail; // add EAGetMail namespace

namespace receiveemail
{
    class Program
    {
        static void Main(string[] args)
        {
            // Create a folder named "inbox" under current directory
            // to store the email file retrieved.
            string curpath = Directory.GetCurrentDirectory();
            string mailbox = String.Format("{0}\\inbox", curpath);

            // If the folder is not existed, create it.
            if (!Directory.Exists(mailbox))
            {
                Directory.CreateDirectory(mailbox);
            }

            MailServer oServer = new MailServer("imap4.emailarchitect.net",
                        "test@emailarchitect.net", "testpassword", ServerProtocol.Imap4);
            MailClient oClient = new MailClient("TryIt");

            // Set IMAP4 server port
            oServer.Port = 143;

            // If your IMAP4 server requires SSL connection,
            // Please add the following codes:
            // oServer.SSLConnection = true;
            // oServer.Port = 993;

            try
            {
                oClient.Connect(oServer);
                MailInfo[] infos = oClient.GetMailInfos();
                for (int i = 0; i < infos.Length; i++)
                {
                    MailInfo info = infos[i];
                    Console.WriteLine("Index: {0}; Size: {1}; UIDL: {2}",
                        info.Index, info.Size, info.UIDL);

                    // Receive email from IMAP4 server
                    Mail oMail = oClient.GetMail(info);

                    Console.WriteLine("From: {0}", oMail.From.ToString());
                    Console.WriteLine("Subject: {0}\r\n", oMail.Subject);

                    // Generate an email file name based on date time.
                    System.DateTime d = System.DateTime.Now;
                    System.Globalization.CultureInfo cur = new
                        System.Globalization.CultureInfo("en-US");
                    string sdate = d.ToString("yyyyMMddHHmmss", cur);
                    string fileName = String.Format("{0}\\{1}{2}{3}.eml",
                        mailbox, sdate, d.Millisecond.ToString("d3"), i);

                    // Save email to local disk
                    oMail.SaveAs(fileName, true);

                    // Mark email as deleted from IMAP4 server.
                    oClient.Delete(info);
                }

                // Quit and purge emails marked as deleted from IMAP4 server.
                oClient.Quit();
            }
            catch (Exception ep)
            {
                Console.WriteLine(ep.Message);
            }

        }
    }
}

Because IMAP4 protocol supports folder access, so we can retrieve email from other mailbox rather than default “INBOX”. POP3 protocol doesn’t support this feature.

[C# Example - Retrieve email from “Deleted Items”]

The following example codes demonstrate how to retrieve emails from “Deleted Items” in an IMAP4 account. In order to run it correctly, please change email server, user, password, folder, file name values.

Note

To get the full sample projects, please refer to Samples section.

using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using EAGetMail; // add EAGetMail namespace

namespace receiveemail
{
    class Program
    {
        static Imap4Folder SearchFolder(Imap4Folder[] folders, string name)
        {
            int count = folders.Length;
            for (int i = 0; i < count; i++)
            {
                Imap4Folder folder = folders[i];
                Console.WriteLine(folder.FullPath);
                // Folder was found.
                if (String.Compare(folder.Name, name) == 0)
                    return folder;

                folder = SearchFolder(folder.SubFolders, name);
                if (folder != null)
                    return folder;
            }
            // No folder found
            return null;
        }

        static void Main(string[] args)
        {
            // Create a folder named "inbox" under current directory
            // to store the email file retrieved.
            string curpath = Directory.GetCurrentDirectory();
            string mailbox = String.Format("{0}\\inbox", curpath);

            // If the folder is not existed, create it.
            if (!Directory.Exists(mailbox))
            {
                Directory.CreateDirectory(mailbox);
            }

            MailServer oServer = new MailServer("imap4.emailarchitect.net",
                        "test@emailarchitect.net", "testpassword", ServerProtocol.Imap4);
            MailClient oClient = new MailClient("TryIt");

            // Set IMAP4 server port
            oServer.Port = 143;

            // If your IMAP4 server requires SSL connection,
            // Please add the following codes:
            // oServer.SSLConnection = true;
            // oServer.Port = 993;

            try
            {
                oClient.Connect(oServer);

                // Lookup folder based name.
                Imap4Folder folder = SearchFolder(oClient.Imap4Folders, "Deleted Items");
                if (folder == null)
                {
                    throw new Exception("Folder was not found");
                }

                // Select this folder
                oClient.SelectFolder(folder);

                // Retrieve emails from selected folder instead of default folder.
                MailInfo[] infos = oClient.GetMailInfos();
                for (int i = 0; i < infos.Length; i++)
                {
                    MailInfo info = infos[i];
                    Console.WriteLine("Index: {0}; Size: {1}; UIDL: {2}",
                        info.Index, info.Size, info.UIDL);

                    // Receive email from IMAP4 server
                    Mail oMail = oClient.GetMail(info);

                    Console.WriteLine("From: {0}", oMail.From.ToString());
                    Console.WriteLine("Subject: {0}\r\n", oMail.Subject);

                    // Generate an email file name based on date time.
                    System.DateTime d = System.DateTime.Now;
                    System.Globalization.CultureInfo cur = new
                        System.Globalization.CultureInfo("en-US");
                    string sdate = d.ToString("yyyyMMddHHmmss", cur);
                    string fileName = String.Format("{0}\\{1}{2}{3}.eml",
                        mailbox, sdate, d.Millisecond.ToString("d3"), i);

                    // Save email to local disk
                    oMail.SaveAs(fileName, true);

                    // Mark email as deleted from IMAP4 server.
                    oClient.Delete(info);
                }

                // Quit and purge emails marked as deleted from IMAP4 server.
                oClient.Quit();
            }
            catch (Exception ep)
            {
                Console.WriteLine(ep.Message);
            }

        }
    }
}

Next Section

At next section I will introduce how to retrieve email from Exchange Server with Web Service protocol.

Appendix

Comments

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