.NET MSN/WLM Now Playing Function

    Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal Hwnd As Integer, ByVal wMsg As Integer, ByVal wParam As Integer, ByVal lParam As Integer) As Integer
    Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Integer
    Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Integer, ByVal hWnd2 As Integer, ByVal lpsz1 As String, ByVal lpsz2 As String) As Integer

    Public Function VarPtr(ByVal o As Object) As Integer
        Dim GC As System.Runtime.InteropServices.GCHandle = System.Runtime.InteropServices.GCHandle.Alloc(o, System.Runtime.InteropServices.GCHandleType.Pinned)
        Dim ret As Integer = GC.AddrOfPinnedObject.ToInt32
        GC.Free()
        Return ret
    End Function

    Private Structure COPYDATASTRUCT
        Dim dwData As Integer
        Dim cbData As Integer
        Dim lpData As Integer
    End Structure

    Private Const WM_COPYDATA As Short = &H4AS

    Public Sub SetMusicInfo(ByRef r_sArtist As String, ByRef r_sAlbum As String, ByRef r_sTitle As String, Optional ByRef r_sWMContentID As String = vbNullString, Optional ByRef r_sFormat As String = "{1} - {0}", Optional ByRef r_bShow As Boolean = True)

        Dim udtData As COPYDATASTRUCT
        Dim sBuffer As String
        Dim hMSGRUI As Integer

        'Total length can not be longer then 256 characters!
        'Any longer will simply be ignored by Messenger.
        sBuffer = "\0Music\0" & System.Math.Abs(CInt(r_bShow)) & "\0" & r_sFormat & "\0" & r_sArtist & "\0" & r_sTitle & "\0" & r_sAlbum & "\0" & r_sWMContentID & "\0" & vbNullChar

        udtData.dwData = &H547S
        udtData.lpData = VarPtr(sBuffer)
        udtData.cbData = Len(sBuffer) * 2

        Do
            hMSGRUI = FindWindowEx(0, hMSGRUI, "MsnMsgrUIManager", vbNullString)

            If (hMSGRUI > 0) Then
                Call SendMessage(hMSGRUI, WM_COPYDATA, 0, VarPtr(udtData))
            End If

        Loop Until (hMSGRUI = 0)

    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        'Displays song info
        SetMusicInfo("Artist", "Album", "Song")

    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

        'Clear song info
        Call SetMusicInfo("", "", "", , , False)

    End Sub