C# - Mark email as read in POP3/IMAP4/EWS/WebDAV¶

using System;
using System.Globalization;
using System.IO;
using EAGetMail; //add EAGetMail namespace

namespace receiveemail
{
    class Program
    {
        // Generate an unqiue email file name based on date time
        static string _generateFileName(int sequence)
        {
            DateTime currentDateTime = DateTime.Now;
            return string.Format("{0}-{1:000}-{2:000}.eml",
                currentDateTime.ToString("yyyyMMddHHmmss", new CultureInfo("en-US")),
                currentDateTime.Millisecond,
                sequence);
        }

        static void Main(string[] args)
        {
            bool isUidlLoaded = false;
            bool isLeaveCopy = true; // leave a copy of message on server.

            // UIDL is the identifier of every email on POP3/IMAP4/Exchange server, to avoid retrieve
            // the same email from server more than once, we record the email UIDL retrieved every time
            // if you delete the email from server every time and not to leave a copy of email on
            // the server, then please remove all the function about uidl.
            // UIDLManager wraps the function to write/read uidl record from a text file.
            UIDLManager oUIDLManager = new UIDLManager();

            try
            {
                // Create a folder named "inbox" under current directory
                // to save the email retrieved.
                string localInbox = string.Format("{0}\\inbox", Directory.GetCurrentDirectory());
                string uidlFile = string.Format("{0}\\uidl.txt", localInbox);

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

                // Load existed uidl records to UIDLManager
                oUIDLManager.Load(uidlFile);
                isUidlLoaded = true;

                MailServer oServer = new MailServer("pop3.emailarchitect.net",
                        "test@emailarchitect.net",
                        "testpassword",
                        ServerProtocol.Pop3);

                // Enable SSL/TLS connection, most modern email server require SSL/TLS by default
                oServer.SSLConnection = true;
                oServer.Port = 995;

                // if your server doesn't support SSL/TLS, please use the following codes
                // oServer.SSLConnection = false;
                // oServer.Port = 110;

                MailClient oClient = new MailClient("TryIt");
                oClient.Connect(oServer);

                MailInfo[] infos = oClient.GetMailInfos();
                Console.WriteLine("Total {0} email(s)\r\n", infos.Length);

                // Remove the local uidl that is not existed on the server,
                oUIDLManager.SyncUIDL(oServer, infos);
                oUIDLManager.Update();

                for (int i = 0; i < infos.Length; i++)
                {
                    MailInfo info = infos[i];
                    if (oUIDLManager.FindUIDL(oServer, info.UIDL) != null)
                    {
                        // This email has been downloaded before
                        continue;
                    }

                    Console.WriteLine("Retrieving {0}/{1}...", i + 1, infos.Length);

                    Mail oMail = oClient.GetMail(info);

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

                    // Generate an unqiue email file name based on date time.
                    string fileName = _generateFileName(i + 1);
                    string fullPath = string.Format("{0}\\{1}", localInbox, fileName);

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

                    if (isLeaveCopy)
                    {
                        // Add uidl to uidl file to avoid we retrieve it next time.
                        oUIDLManager.AddUIDL(oServer, info.UIDL, fileName);
                    }
                    else
                    {
                        Console.WriteLine("Deleting ...");
                        oClient.Delete(info);

                        // Remove UIDL from local uidl file.
                        oUIDLManager.RemoveUIDL(oServer, info.UIDL);
                    }
                }

                // Quit and expunge emails marked as deleted from POP3 server.
                oClient.Quit();
                Console.WriteLine("Completed!");
            }
            catch (Exception ep)
            {
                Console.WriteLine(ep.Message);
            }

            // Update the uidl list to local uidl file and then we can load it next time.
            if (isUidlLoaded)
            {
                oUIDLManager.Update();
            }
        }
    }
}

using System;
using System.Globalization;
using System.IO;
using EAGetMail; //add EAGetMail namespace

namespace receiveemail
{
    class Program
    {
        // Generate an unqiue email file name based on date time
        static string _generateFileName(int sequence)
        {
            DateTime currentDateTime = DateTime.Now;
            return string.Format("{0}-{1:000}-{2:000}.eml",
                currentDateTime.ToString("yyyyMMddHHmmss", new CultureInfo("en-US")),
                currentDateTime.Millisecond,
                sequence);
        }

        static void Main(string[] args)
        {
            try
            {
                // Create a folder named "inbox" under current directory
                // to save the email retrieved.
                string localInbox = string.Format("{0}\\inbox", Directory.GetCurrentDirectory());
                // If the folder is not existed, create it.
                if (!Directory.Exists(localInbox))
                {
                    Directory.CreateDirectory(localInbox);
                }

                MailServer oServer = new MailServer("imap.emailarchitect.net",
                        "test@emailarchitect.net",
                        "testpassword",
                        ServerProtocol.Imap4);

                // Enable SSL/TLS connection, most modern email server require SSL/TLS by default
                oServer.SSLConnection = true;
                oServer.Port = 993;

                // if your server doesn't support SSL/TLS, please use the following codes
                // oServer.SSLConnection = false;
                // oServer.Port = 143;

                MailClient oClient = new MailClient("TryIt");
                oClient.Connect(oServer);

                // retrieve unread/new email only
                oClient.GetMailInfosParam.Reset();
                oClient.GetMailInfosParam.GetMailInfosOptions = GetMailInfosOptionType.NewOnly;

                MailInfo[] infos = oClient.GetMailInfos();
                Console.WriteLine("Total {0} unread email(s)\r\n", infos.Length);
                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 unqiue email file name based on date time.
                    string fileName = _generateFileName(i + 1);
                    string fullPath = string.Format("{0}\\{1}", localInbox, fileName);

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

                    // mark unread email as read, next time this email won't be retrieved again
                    if(!info.Read)
                    {
                        oClient.MarkAsRead(info, true);
                    }

                    // if you don't want to leave a copy on server, please use
                    // oClient.Delete(info);
                    // instead of MarkAsRead
                }

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