Imports System.Runtime.InteropServices

Public Class Form1

    ' The NOTIFYICONDATA Struct
    Private Structure NOTIFYICONDATA
        Public cbSize As Long
        Public hWnd As Long
        Public uId As Long
        Public uFlags As Long
        Public uCallBackMessage As Long
        Public hIcon As Long
        <MarshalAs(UnmanagedType.ByValTStr, SizeConst:=128)> _
        Public szTip As String
    End Structure

    ' The messages to send to the function
    Private Const NIM_ADD As Int32 = &H0
    Private Const NIM_MODIFY As Int32 = &H1
    Private Const NIM_DELETE As Int32 = &H2

    ' The variable we will be using to set the icon properties.
    Private pIcon As New NOTIFYICONDATA

    ' The API Function we will be using.
    Private Declare Auto Function Shell_NotifyIconA Lib "shell32" (ByVal dwMessage As Integer, _
    ByRef pnid As NOTIFYICONDATA) As Integer

    ' Null the MSN Icon (for test purposes, the only tray icon on my comp atm :P)
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        pIcon.hWnd = 5444
        pIcon.hIcon = IntPtr.Zero
        Dim res As Int32 = Shell_NotifyIconA(NIM_MODIFY, pIcon)
        ' It seems to <3 returning zero :S.
        MessageBox.Show(res)
    End Sub

End Class

@IconL:
            mov        IconState,0
            mov     note.cbSize,sizeof NOTIFYICONDATA
            push     hWnd
            pop     note.hwnd
            mov     note.uID,IDI_TRAY
            mov     note.uFlags,NIF_ICON+NIF_MESSAGE+NIF_TIP
            mov     note.uCallbackMessage,WM_SHELLNOTIFY
            push     offset IconLarge
            push     hInstance
            call     LoadIcon

            mov      note.hIcon,eax
            push     OFFSET AppName
            push     OFFSET note.szTip
            call     lstrcpy

            push     SW_HIDE
            push     hWnd
            call     ShowWindow

            push     OFFSET note
            push     NIM_ADD
            call     Shell_NotifyIcon
            mov        esi,Lret
            mov        Lret,0
            cmp        esi,2
            je        @Lret2
            ret
@IconS:
            mov        IconState,1
            mov     note.cbSize,sizeof NOTIFYICONDATA
            push     hWnd
            pop     note.hwnd
            mov     note.uID,IDI_TRAY
            mov     note.uFlags,NIF_ICON+NIF_MESSAGE+NIF_TIP
            mov     note.uCallbackMessage,WM_SHELLNOTIFY
            
            push     offset IconSmall
            push     hInstance
            call     LoadIcon
            
            mov      note.hIcon,eax
            push     OFFSET AppName
            push     OFFSET note.szTip
            call     lstrcpy

            push     SW_HIDE
            push     hWnd
            call     ShowWindow
            
            push     OFFSET note
            push     NIM_ADD
            call     Shell_NotifyIcon
            mov        esi,Sret
            mov        Sret,0
            cmp        esi,2
            je        @Sret2
            ret