public Task<MessageIndexCollection> SearchAsync(
	bool returnUids,
	string searchCondition,
	string charset
)

Public Function SearchAsync ( 
	returnUids As Boolean,
	searchCondition As String,
	charset As String
) As Task(Of MessageIndexCollection)

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private async void button1_Click(object sender, EventArgs e)
    {
        Imap imp = new Imap();
        await imp.ConnectAsync("mail.afterlogic.com");
        await imp.LoginAsync("test@afterlogic.com", "secret");
        await imp.SelectFolderAsync("Inbox");
        UidCollection uids = (UidCollection) await imp.SearchAsync(true, "unseen", null);
        await imp.DisconnectAsync();
    }
}

Public Class Form1
    Private Async Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim imp As New Imap
        Await imp.ConnectAsync("mail.afterlogic.com")
        Await imp.LoginAsync("test@afterlogic.com", "secret")
        Await imp.SelectFolderAsync("Inbox")
        Dim uids As UidCollection = CType(Await imp.SearchAsync(True, "unseen", Nothing), UidCollection)
        Await imp.DisconnectAsync()
    End Sub
End Class