Use GetMailboxStatAsync methods to asynchronously obtain information about a mailbox. These methods get information about the mailbox asynchronously with execution occurring on a new thread, therefore they allow your next line of code to execute immediately.

In Task-based Asynchronous programs, the single asynchronous method represents the initiation and completion of an asynchronous operation. You may create the continuation code either explicitly, through methods on the Task class (for example, ContinueWith) or implicitly, by using language support built on top of continuations (for example, await in C#, Await in Visual Basic).

In Event-based Asynchronous programs, the event GetMailboxStatCompleted is raised when the GetMailboxStatAsync method completes. In the event handler method of the GetMailboxStatCompleted, you can check if there were any errors by using the Error property of the event data object.

The following example demonstrates how to asynchronously obtain information about a mailbox:

Task-based approach

using System;
using ComponentPro;
using ComponentPro.Net.Mail;

...

// Create a new instance of the Pop3 class.
Pop3 client = new Pop3();

// Connect to the server.
client.Connect("myserver");

// Or you can specify the POP3 port with 
// client.Connect("myserver", 110); 
 
// Login to the server.
client.Authenticate("user", "password");

// ... 
 
// Obtain mainbox information.
Pop3MailboxStat stat = await client.GetMailboxStatAsync();

// Do something here ...

Console.WriteLine("The number of recent messages: " + stat.MessageCount);
Console.WriteLine("Mailbox Size: " + stat.Size);

// Do something here ... 
 
// Disconnect.
client.Disconnect();

Imports ComponentPro
Imports ComponentPro.Net.Mail

...

' Create a new instance of the Pop3 class. 
Dim client As New Pop3()

' Connect to the server.
client.Connect("myserver")

' Or you can specify the POP3 port with 
' client.Connect("myserver", 110); 
 
' Login to the server.
client.Authenticate("user", "password")

' ... 
 
' Obtain mainbox information. 
Dim stat As Pop3MailboxStat = Await client.GetMailboxStatAsync()

' Do something here ...

Console.WriteLine("The number of recent messages: " & stat.MessageCount)
Console.WriteLine("Mailbox Size: " & stat.Size)

' Do something here ... 
 
' Disconnect.
client.Disconnect()

Event-based approach

using System;
using ComponentPro;
using ComponentPro.Net.Mail;

...

public void DoGetMailboxAsync()
{
    // Create a new instance of the Pop3 class. 
    Pop3 client = new Pop3();

    // Connect to the server. 
    client.Connect("myserver");

    // Or you can specify the POP3 port with 
    // client.Connect("myserver", 110); 
 
    // Login to the server. 
    client.Authenticate("user", "password");

    // ... 
 
    // Register an event handler. 
    client.GetMailboxStatCompleted += client_GetMailboxInfoCompleted;

    // Obtain mainbox information. 
    client.GetMailboxStatAsync();

    // Do something here ... 
 
    // Disconnect. 
    client.Disconnect();
}

void ShowMailboxStat(Pop3MailboxStat stat)
{
    Console.WriteLine("The number of recent messages: " + stat.MessageCount);
    Console.WriteLine("Mailbox Size: " + stat.Size);
}

void client_GetMailboxInfoCompleted(object sender, ExtendedAsyncCompletedEventArgs<Pop3MailboxStat> e)
{
    Pop3 client = (Pop3)sender;
    if (e.Error != null)
    {
        Console.WriteLine("Error: " + e.Error.ToString());
    }
    else 
        ShowMailboxStat(e.Result);
}

Imports ComponentPro
Imports ComponentPro.Net.Mail

...

Public Sub DoGetMailboxAsync()
    ' Create a new instance of the Pop3 class. 
    Dim client As New Pop3()

    ' Connect to the server. 
    client.Connect("myserver")

    ' Or you can specify the POP3 port with 
    ' client.Connect("myserver", 110); 
 
    ' Login to the server. 
    client.Authenticate("user", "password")

    ' ... 
 
    ' Register an event handler. 
    AddHandler client.GetMailboxStatCompleted, AddressOf client_GetMailboxInfoCompleted

    ' Obtain mainbox information. 
    client.GetMailboxStatAsync()

    ' Do something here ... 
 
    ' Disconnect. 
    client.Disconnect()
End Sub 
 
Private Sub ShowMailboxStat(ByVal stat As Pop3MailboxStat)
    Console.WriteLine("The number of recent messages: " & stat.MessageCount)
    Console.WriteLine("Mailbox Size: " & stat.Size)
End Sub 
 
Private Sub client_GetMailboxInfoCompleted(ByVal sender As Object, ByVal e As ExtendedAsyncCompletedEventArgs(Of Pop3MailboxStat))
    Dim client As Pop3 = CType(sender, Pop3)
    If e.Error IsNot Nothing Then 
        Console.WriteLine("Error: " & e.Error.ToString())
    Else 
        ShowMailboxStat(e.Result)
    End If 
End Sub