[ObsoleteAttribute("This method is obsolete in .NET 4.5+. Use SelectFolderAsync instead.")]
public IAsyncResult BeginSelectFolder(
	string folderName,
	bool readOnly,
	AsyncCallback callback,
	Object state
)

<ObsoleteAttribute("This method is obsolete in .NET 4.5+. Use SelectFolderAsync instead.")>
Public Function BeginSelectFolder ( 
	folderName As String,
	readOnly As Boolean,
	callback As AsyncCallback,
	state As Object
) As IAsyncResult

using System;
using MailBee;
using MailBee.ImapMail;

class Sample
{
    // A callback function.
    private static void SelectFolderCallback(IAsyncResult result)
    {
        Imap imp = (Imap)result.AsyncState;
        imp.EndSelectFolder();
        Console.WriteLine("Overall size of all messages in the inbox is " +
            imp.GetFolderSize() + " bytes");
    }

    // The actual code.
    static void Main(string[] args)
    {
        Imap imp = new Imap();

        imp.Connect("imap4.somehost.com");
        imp.Login("jdoe@somehost.com", "secret");

        // Initiate an asynchronous select folder attempt.
        IAsyncResult ar = imp.BeginSelectFolder("Inbox", false,
            new AsyncCallback(SelectFolderCallback), imp);

        // Simulate some lengthy work here. At the same time,
        // folder selection is executed on another thread.
        System.Threading.Thread.Sleep(3000);

        // If the folder selection attempt is still in progress,
        // then wait until it's finished.
        while (imp.IsBusy) ar.AsyncWaitHandle.WaitOne();

        // Disconnect from the server.
        imp.Disconnect();
    }
}

Imports System
Imports MailBee
Imports MailBee.ImapMail

Module Sample

    ' A callback function.
    Private Sub SelectFolderCallback(ByVal result As IAsyncResult)
        Dim imp As Imap = CType(result.AsyncState, Imap)
        imp.EndSelectFolder()
        Console.WriteLine("Overall size of all messages in the inbox is " & _
            imp.GetFolderSize() & " bytes")
    End Sub

    Sub Main()
        ' The actual code (put it into a method of your class)
        Dim imp As New Imap

        ' Connect to the server and log in the account.
        imp.Connect("imap4.company.com")
        imp.Login("jdoe@company.com", "secret")

        ' Initiate an asynchronous select folder attempt.
        Dim ar As IAsyncResult = imp.BeginSelectFolder("Inbox", False, _
            New AsyncCallback(AddressOf SelectFolderCallback), imp)

        ' Simulate some lengthy work here. At the same time,
        ' folder selection is executed on another thread.
        System.Threading.Thread.Sleep(3000)

        ' If the folder selection attempt is still in progress,
        ' then wait until it's finished.
        While imp.IsBusy
            ar.AsyncWaitHandle.WaitOne()
        End While

        ' Disconnect from the server.
        imp.Disconnect()
    End Sub
End Module